Ensure all formulae/casks are audited regularly

[MikeMcQuaid]

Verification

• This issue's title and/or description do not reference a single formula e.g. brew install wget. If they do, open an issue at https://github.com/Homebrew/homebrew-core/issues/new/choose instead.

Provide a detailed description of the proposed feature

We have a scheduled job that runs every day for homebrew-core (https://github.com/Homebrew/homebrew-core/blob/master/.github/workflows/scheduled.yml)
and for homebrew-cask (https://github.com/Homebrew/homebrew-cask/blob/master/.github/workflows/scheduled.yml).

It picks a random selection of formulae/casks and audits them, posting issues to e.g. Homebrew/homebrew-core#139929 for homebrew-core.

Ideally, this would be changed so:

• there is no randomness but instead we audit the same (or: as close to the same as possible) formulae/casks on a given day in a time period
• in a given time period (e.g. weekly/fortnightly/monthly, depending on rate limits) we can guarantee complete coverage of all formulae/casks

What is the motivation for the feature?

Ensure that every formula/cask is audited regularly rather than a random selection.

How will the feature be relevant to at least 90% of Homebrew users?

Addressing cases like https://github.com/orgs/Homebrew/discussions/5954

What alternatives to the feature have been considered?

• The status quo
• Trying to audit everything every time (likely problematic from a rate limit perspective)

[carlocab]

• there is no randomness but instead we audit the same (or: as close to the same as possible) formulae/casks on a given day in a time period

This is already the case for formulae. See Homebrew/homebrew-core#192485. Each formulae is audited roughly every 150 days (but that will happen less often as more formulae are added).

[MikeMcQuaid]

@carlocab Oh nice, thanks!

Would be great if we could (somehow?) get this down to once a month at most, even if this required e.g. dedicated CI capacity to do this.

[carlocab]

We would have to audit 250 formulae a day to get there, and increase that as more formulae are added.

[Bo98]

Instead of running the job once a day we can probably scatter it a few times over a day.