CMakeDetermineCompilerId: Test without COMPILER_ID_FLAGS if REQUIRE_SUCCESS
If we REQUIRE_SUCCESS, i.e. TEST_FLAGS_FIRST must work, we need to also try without user flags.
Fixes #21869 (closed).
Backport: release
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If we REQUIRE_SUCCESS, i.e. TEST_FLAGS_FIRST must work, we need to also try without user flags.
Fixes #21869 (closed).
Backport: release