Create LeakSanitizer suppression rules to run with detect_leaks=1

[disconnect3d]

Hi,

Atheris is currently recommended to run with ASan's detect_leaks=0 as per native_extension_fuzzing.md#leak-detection.

I believe this can be fixed/changed by suppressing the Python initialization's memory leaks using the LeakSanitizer suppression rules.

We should implement those rules and recommend users to run with them, or, make them somehow "builtin" (so they are applied automagically) if there is such an option.