Minor package cleanup

[gwynne]

• Disable CodeQL CI, as GitHub hasn't fixed it yet
• Clean up badges in README
• Include latest revisions to images and theme settings in DocC catalog
• Make LOG_LEVEL env var work in tests
• Default the log level in tests to .info to match original (broken) logic

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 61.78%. Comparing base (dc9caf8) to head (d98d68a).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #464 +/- ## ========================================== - Coverage 61.82% 61.78% -0.04% ========================================== Files 125 125 Lines 10019 10019 ========================================== - Hits 6194 6190 -4 - Misses 3825 3829 +4 ``` [see 2 files with indirect coverage changes](https://app.codecov.io/gh/vapor/postgres-nio/pull/464/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor)