Every time that we bump PHP versions here and there (new requirements or new php versions supported) we have to amend the GHA CI integration (.github/workflows/push.yml to stop using old PHP versions or start using new ones.

And we always have some discussion about which PHP versions should be used for MySQL and PostgreSQL steps there. See for example MDL-73018, happening today.

The current strategy (that is clear in my brain and maybe also in the issue that it was incepted) is as simple as:

1. MySQL always run with the lowest PHP version supported.
2. PostgreSQL always run with the highest PHP version supported.

So this issues is as simple as document in code the strategy above, only master, basically adding something like:

diff --git a/.github/workflows/push.yml b/.github/workflows/push.yml

index 9c055dbf767..38a90ec6262 100644

--- a/.github/workflows/push.yml

+++ b/.github/workflows/push.yml

@@ -54,10 +54,12 @@ jobs:

       fail-fast: false

       matrix:

         include:

+          # MySQL always with the lowest PHP supported branch.

           - os: ubuntu-22.04

             php: 8.0

             extensions:

             db: mysqli

+          # PostgreSQL always with the highest PHP supported branch.

           - os: ubuntu-22.04

             php: 8.1

             db: pgsql

And done.