fixup! codeql: run static analysis as part of CI builds

As of b133d30 (github: simplify computation of the job's distro,
2025-01-10), the `apt-get update` call that is guarded by `$distro` in
the `ci/install-dependencies.sh` script requires the `CI_JOB_IMAGE`
variable to set correctly (which is used to initialize `distro` in the
GitHub Actions-specific part at the top of `ci/lib.sh`).

Let's do the same in the CodeQL workflow.

Noticed-by: Derrick Stolee <stolee@gmail.com>
Noticed-by: Tyrie Vella <tyrielv@gmail.com>
Noticed-by: Matthew John Cheetham <mjcheetham@outlook.com>
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

Author: dscho

.github/workflows/codeql.yml

@@ -30,6 +30,7 @@ jobs:
         if: matrix.language == 'cpp'
         env:
           jobname: codeql
+          CI_JOB_IMAGE: ubuntu-latest
 
       # Initializes the CodeQL tools for scanning.
       - name: Initialize CodeQL