GeezerVison

pythonGH-99859 introduced new buildbot failures, as reported [here](python#91054 (comment)).

I was able to reproduce the failures with:

```
./python.exe -m test -v test_capi.test_watchers -m "*TestCodeObjectWatchers*" -R 3:3
```

The root cause appears to be to static events counters used in the tests,
when running the tests with repetitions (using the same interpreter state),
the counts from the first test run affected the next runs.

This fixes it by resetting the counts when adding and clearing test watchers.