New exclude_regex Filter to Address False Positives on Password Tests

[comc]

Is your feature request related to a problem? Please describe.
Consistent issues arise on false positives of "token"-matched variable names in tests B105 and B106.

See: #498, #842, #843, #211

Describe the solution you'd like
It would be useful to have an exclude_regex field available to filter variable names, and not just excludes at the files and tests level.

Describe alternatives you've considered

• exclude and exclude_dirs skips entire files/folders and are too permissive
• skips completely skips entire tests and are too permissive
• # nosec entries clutter source code when there are excessive false positives

Additional context
Ideally, coupling an exclude_regex with exclude would be ideal granularity.

Example pyproject.toml to exclude "token" variable name filtering only in files under "tests/" folders for B106:

[tool.bandit.hardcoded_password_funcarg]
exclude_dirs = ["tests"]
exclude_regex = ["token"]

👍?