Convert GitHub branch protections to rulesets

[marcoieni]

To have more flexibility and configurability, we want to migrate from classic GitHub branch protection rules to GitHub Rulesets across all Rust Project repositories.
Rulesets are the new way GitHub wants their users to configure tag and branch protections. The support for branch protections is already limited (eg you can't configure merge queues like noticed in #1735).

Related PRs:

• Remove branch protections from crates.io repository #2046
• feat: implement rulesets for branch protections #2168
• feat: set GitHub actions integration ID for ruleset CI checks #2200
• Fix synchronization of rulesets #2298
• rulesets: implement allowed-merge-apps #2304
• enable crates-io rulesets #2311
• add more strict rulesets defaults #2314
• use BTreeSet for ruleset rules #2319
• move rustfmt to GitHub rulesets #2323
• manage "allow force push" in branch protections #2324
• simplify default ruleset name #2325
• don't show false diff in sync logs #2329
• prepare for moving cargo from branch protections to rulesets #2333
• move cargo to rulesets #2335
• apply github defaults to ruleset merge queues #2336
• enable merge queues for repositories using default settings #2350
• use rulesets in the rust repo #2327
• add merge queue settings #2353
• configure all merge queues #2355
• add require_up_to_date_branches to v1 api #2364
• convert more repos to rulesets #2370
• add support for require conversation resolution #2374
• convert more repositories to rulesets #2375
• validate merge queue branch pattern #2378
• branches: support require linear history #2383
• convert four repositories to rulesets #2384
• rulesets: log when default fields change #2385
• convert two repositories to rulesets #2386
• convert five repositories to rulesets #2387
• convert the blog to rulesets #2389
• use rulesets by default #2397
• delete disable-rulesets-repos config field #2433
• remove support for branch protections #2434
• rename branch-protections to rulesets #2436