qa/{asan,lsan}.supp: suppress Python module and libstdc++ false positives

qa/{asan,lsan}.supp: suppress Python module and libstdc++ false positives

Add suppression rules for two categories of false positive warnings
encountered during ASan-enabled testing:

1. PyModule_ExecDef memory leaks: ASan incorrectly interprets Python's
   module loading behavior as memory leaks when the interpreter loads
   extension modules.

2. __cxa_throw interception failures: ASan's interceptor cannot properly
   intercept exception handling when libstdc++.so is loaded after the
   ASan shared library, causing CHECK failures.

3. ErasureCodePluginRegistry::load:
   `ceph::ErasureCodePluginRegistry::load()` is known to leak, as we
   don't free the memory allocated by the ec plugins which are
   registered in the `ErasureCodePluginRegistry` singleton. this is a
   known issue, but since the `ErasureCodePluginRegistry` instance is a
   singleton. we can live with it. in this change, we add the rule to
   suppress the leak report from LeakSanitizer. this rule also exist in
   qa/valgrind.supp.

All warnings are confirmed false positives that should be suppressed
to reduce noise in test output.

Example warnings:

```
Direct leak of 3264 byte(s) in 1 object(s) allocated from:
    #0 0x7f6027d20cb5 in malloc /usr/src/debug/gcc/gcc/libsanitizer/asan/asan_malloc_linux.cpp:67
    #1 0x7f60277557ad  (/usr/lib/libpython3.13.so.1.0+0x1557ad) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #2 0x7f6027756067  (/usr/lib/libpython3.13.so.1.0+0x156067) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #3 0x7f60278471a0  (/usr/lib/libpython3.13.so.1.0+0x2471a0) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #4 0x7f602774d031  (/usr/lib/libpython3.13.so.1.0+0x14d031) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #5 0x7b60234093bb in __Pyx_modinit_type_init_code.constprop.0 /home/kefu/dev/ceph/build/src/pybind/rados/rados.c:82066
    #6 0x7b602340a826 in __pyx_pymod_exec_rados /home/kefu/dev/ceph/build/src/pybind/rados/rados.c:82755
    #7 0x7f6027856777 in PyModule_ExecDef (/usr/lib/libpython3.13.so.1.0+0x256777) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #8 0x7f602785baa3  (/usr/lib/libpython3.13.so.1.0+0x25baa3) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #9 0x7f6027793df2  (/usr/lib/libpython3.13.so.1.0+0x193df2) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #10 0x7f6027777cbe in _PyEval_EvalFrameDefault (/usr/lib/libpython3.13.so.1.0+0x177cbe) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #11 0x7f60277957de  (/usr/lib/libpython3.13.so.1.0+0x1957de) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #12 0x7f60277d11b9 in PyObject_CallMethodObjArgs (/usr/lib/libpython3.13.so.1.0+0x1d11b9) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #13 0x7f60277d0ee4 in PyImport_ImportModuleLevelObject (/usr/lib/libpython3.13.so.1.0+0x1d0ee4) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #14 0x7f6027779c0c in _PyEval_EvalFrameDefault (/usr/lib/libpython3.13.so.1.0+0x179c0c) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #15 0x7f602784e2c8 in PyEval_EvalCode (/usr/lib/libpython3.13.so.1.0+0x24e2c8) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #16 0x7f602788c88b  (/usr/lib/libpython3.13.so.1.0+0x28c88b) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #17 0x7f602788985c  (/usr/lib/libpython3.13.so.1.0+0x28985c) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #18 0x7f6027886f57  (/usr/lib/libpython3.13.so.1.0+0x286f57) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #19 0x7f6027886211  (/usr/lib/libpython3.13.so.1.0+0x286211) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #20 0x7f6027885b82  (/usr/lib/libpython3.13.so.1.0+0x285b82) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #21 0x7f6027883e50 in Py_RunMain (/usr/lib/libpython3.13.so.1.0+0x283e50) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #22 0x7f602783bbea in Py_BytesMain (/usr/lib/libpython3.13.so.1.0+0x23bbea) (BuildId: bea05fc2c8bd66145b159f10dcd810ebe813af39)
    #23 0x7f6027227674  (/usr/lib/libc.so.6+0x27674) (BuildId: 4fe011c94a88e8aeb6f2201b9eb369f42b4a1e9e)
    #24 0x7f6027227728 in __libc_start_main (/usr/lib/libc.so.6+0x27728) (BuildId: 4fe011c94a88e8aeb6f2201b9eb369f42b4a1e9e)
    #25 0x55dae17e6044 in _start (/usr/bin/python3.13+0x1044) (BuildId: 8c0dc848f5b978c56ebeb07255bb332b4b37ae4e)
```

```
AddressSanitizer: CHECK failed: asan_interceptors.cpp:335 "((__interception::real___cxa_throw)) != (0)" (0x0, 0x0) (tid=3246455)
    #0 0x7f345ea81979 in CheckUnwind ../../../../src/libsanitizer/asan/asan_rtl.cpp:69
    #1 0x7f345eaa790d in __sanitizer::CheckFailed(char const*, int, char const*, unsigned long long, unsigned long long) ../../../../src/libsanitizer/sanitizer_common/sanitizer_termination.cpp:86
    #2 0x7f345e9e1d54 in __interceptor___cxa_throw ../../../../src/libsanitizer/asan/asan_interceptors.cpp:335
    #3 0x7f345e9e1d54 in __interceptor___cxa_throw ../../../../src/libsanitizer/asan/asan_interceptors.cpp:334
    #4 0x7f3458623def in void boost::throw_exception<boost::bad_lexical_cast>(boost::bad_lexical_cast const&) /opt/ceph/include/boost/throw_exception.hpp:165
    #5 0x7f345997ad3b in void boost::conversion::detail::throw_bad_cast<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, unsigned long>() /opt/ceph/include/boost/lexical_cast/bad_lexical_cast.hpp:93
    #6 0x7f3459979d35 in unsigned long boost::lexical_cast<unsigned long, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > >(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /opt/ceph/include/boost/lexical_cast.hpp:43`
```

Signed-off-by: Kefu Chai <tchaikov@gmail.com>