Turn pr bot on for remaining common labels

[damccorm]

This turns on the PR bot for the remaining few labels (Java/Io/Build) that get a lot of PR traffic. I did my best to come up with an initial set of reviewers to be round robined to, but it was mostly based on manual inspection. The bot should eventually update that list anyways.

Closes #21421

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[damccorm]

R: @Abacn

[Abacn]

Do we still need these date filters (see below)
The Get request in processNewPrs will get at most 30 latest created open prs (according to https://docs.github.com/en/rest/pulls/pulls#list-pull-requests)

[damccorm]

Good question! We do need it though - if you look at

beam/scripts/ci/pr-bot/processNewPrs.ts

Lines 307 to 313 in 53c3ffb

	let openPulls = await githubClient.paginate(
	"GET /repos/{owner}/{repo}/pulls",
	{
	owner: REPO_OWNER,
	repo: REPO,
	}
	);

its called with paginate which automatically pulls all the pages of results (using continuation tokens). So it does get all open pulls. Otherwise I would've just called the octokit method for listing pulls directly instead of using the rest API.

Also, for posterity, this filter is so that the bot doesn't activate on pulls where reviews are already in progress

[Abacn]

got it. LGTM