tests/test-erasure-code: spin off eio tests into another testsuite

tests/test-erasure-code: spin off eio tests into another testsuite

* since the eio tests crashes some of the OSD nodes, before the
  change, the tests try to undo the crash before moving on, so it
  won't interfere with following tests. a more robust/clean way to
  do this is to isolate individual tests in a sandbox, so each eio
  test will have its own:
    setup + inject + verify crash + teardown
  cycle. this change helps to remove the cleanup/undo steps in
  invidual test.
* update the disabled tests accordingly.
* use a minimum set of OSDs and R-S(2,1) for the testing to speed
  up the test.
* add the new testsuite to check_SCRIPTS

Fixes: #11693
Signed-off-by: Kefu Chai <kchai@redhat.com>