Fix example code in Active Job guide [ci skip]
Merge pull request #16659 from y-yagi/patch-4

Fix example code in Active Job guide [ci skip]
Don't trim excess whitespace in pg #columns_for_distinct

Fixes #16623 introduced by https://github.com/rails/rails/commit/3d5a2019bcccc6fb01bee4811ca669f4383edb51
Fix guide anchor generation logic.

This could use in any translation because it's not limited to `[^a-z0-9]`.

Verify after this change, all guides still have same anchors.

[Robin Dupret & Juanito Fatas]
Merge pull request #16649 from Agis-/pg-columns-for-distinct

Fix postgresql adapter #columns_for_distinct trimming whitespace it shouldn't
CHANGELOG & improvements to #16649

* Require either FIRST or LAST qualifier for "NULLS ..."
* Require whitespace before "NULLS ..."
Merge pull request #16667 from JuanitoFatas/patch/anchor-generation

Fix guide anchor generation logic.
Raise ActiveJob::SerializationError when cannot serialize job arguments