Run jobs on GitLab CI branch tests

The initial GitLab CI commit only enabled pipelines for MRs, so repurposing this issue to add pipelines on push and also manually via the web UI.

Added three extra triggers to the default PHP 8.2/MySQL 8 job:

• push for branch pushes
• schedule so we can replicate DrupalCI scheduled pipelines
• web so maintainers can manually trigger runs if needed

The MR changes look good to me. It's targeting just the "project" namespace for other manual (web), schedule or push, which makes sense as we don't want/need that in forks.

RTBC.

Committed/pushed to 11.x, leaving this open for more branch test fun.

CI_MERGE_REQUEST_TARGET_BRANCH_NAME is only set for MRs; CI_COMMIT_BRANCH is only set for branch pushes, so we can concatenate the variables and get the correct value where we need it.

The cspell job tries to look for the set of modified files, which doesn't make sense in a branch run, so we need to figure out what we should do here - a full run of cspell?

Think this can be marked as fixed now and matrix jobs and cspell have their own individual followups.

Automatically closed - issue fixed for 2 weeks with no activity.