Debug renovate configuration to reduce PR noise

[ca-scribner]

our renovate setup is supposed to:

• ignore requirements*.txt files
• execute pip-compile on these matching files, producing a single PR with all packages that change during this step

But we still see renovate working on a single package. We should debug this, and apply whatever fixes we find to all our repos. The renovate bot which executes these tests is managed organization wide, but should have logs that we can access to better understand what is going on.

Also proposed in the same effort is to move /renovate.json to .github/renovate.json to reduce clutter.

[ca-scribner]

See also this internal conversation for more notes