cmake: move rgw_lua_request.cc from rgw_common target to rgw_a

cmake: move rgw_lua_request.cc from rgw_common target to rgw_a

resolves a clang linker error where `rgw::lua::request::RequestLog()`
from rgw_lua_request.cc (in rgw_common) looks for `rgw_log_op()` from
rgw_log.cc (in rgw_a)

rgw_a depends on rgw_common, not the other way around. so this moves
rgw_lua_request.cc into the same target as rgw_log.cc

lua is now a public dependency of rgw_common so it's not hidden from
rgw_a or unit tests

Signed-off-by: Casey Bodley <cbodley@redhat.com>