Fixes 5445: Add checks for feature flags

[kkmurerwa]

Explanation

Fixes #5445: When merged, this PR will;

• Introduce a check to ensure new feature flags are added into the FeatureFlagsLogger
• Add any existing flags that are currently not being logged
• Add the feature_flags_check.sh file to static_checks.sh so that it can be run locally

Essential Checklist

• The PR title and explanation each start with "Fix #bugnum: " (If this PR fixes part of an issue, prefix the title with "Fix part of #bugnum: ...".)
• Any changes to scripts/assets files have their rationale included in the PR explanation.
• The PR follows the style guide.
• The PR does not contain any unnecessary code changes from Android Studio (reference).
• The PR is made from a branch that's not called "develop" and is up-to-date with "develop".
• The PR is assigned to the appropriate reviewers (reference).

[adhiamboperes]

Thanks @kkmurerwa! Overall implementation looks great, but I have a comment re- Function Scoping and Style Consistency: You use both function declarations and the function keyword. It's generally better to stick with one style for consistency.

PTAL.

[kkmurerwa]

@adhiamboperes I have made the changes requested. PTAL and let me know if further modifications are required.

[adhiamboperes]

LGTM, thanks @kkmurerwa!