Change `build` and `codeql-analysis` triggers

Since apache/logging-parent#500 has been merged, workflow runs no longer need to be triggered by PR events of type `ready_for_review`. We therefore remove the `pull_request.types` filter entirely, which restores the default event types.

We also simplify the `branches` filters on the `push` and `pull_request` triggers. Since this workflow file lives on `2.x`, these filters only affect `2.x` itself and branches created from it:

- For `push`: only `release/2*` branches automatically inherit these workflows. We drop `2.25.x` (in `build`) and `main` (in `codeql-analysis`), since those entries would only be useful if we were to branch `2.25.x` or `main` anew from `2.x`. Keeping them would confuse readers of the workflow file.
- For `pull_request`: all branches will run these workflows if a PR is opened against them (e.g. "stacked" PRs opened against the branch of another PR).