Apply ubuntu-slim migration to this repository

Migrate lightweight workflow jobs to use the cost-effective ubuntu-slim
runner as per the updated templates.

Signed-off-by: Leandro Lucarella <[email protected]>

Author: llucax

.github/workflows/auto-dependabot.yaml

@@ -10,7 +10,7 @@ permissions:
 jobs:
   auto-merge:
     if: github.actor == 'dependabot[bot]'
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     steps:
       - name: Auto-merge Dependabot PR
         uses: frequenz-floss/dependabot-auto-approve@3cad5f42e79296505473325ac6636be897c8b8a1 # v1.3.2

.github/workflows/ci.yaml

@@ -60,7 +60,7 @@ jobs:
     needs: ["nox"]
     # We skip this job only if nox was also skipped
     if: always() && needs.nox.result != 'skipped'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     env:
       DEPS_RESULT: ${{ needs.nox.result }}
     steps:
@@ -161,7 +161,7 @@ jobs:
     needs: ["test-installation"]
     # We skip this job only if test-installation was also skipped
     if: always() && needs.test-installation.result != 'skipped'
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     env:
       DEPS_RESULT: ${{ needs.test-installation.result }}
     steps:
@@ -276,7 +276,7 @@ jobs:
       # discussions to create the release announcement in the discussion forums
       contents: write
       discussions: write
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     steps:
       - name: Download distribution files
         uses: actions/download-artifact@v6
@@ -318,7 +318,7 @@ jobs:
   publish-to-pypi:
     name: Publish packages to PyPI
     needs: ["create-github-release"]
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     permissions:
       # For trusted publishing. See:
       # https://blog.pypi.org/posts/2023-04-20-introducing-trusted-publishers/

.github/workflows/dco-merge-queue.yml

@@ -5,7 +5,7 @@ on:
 
 jobs:
   DCO:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     if: ${{ github.actor != 'dependabot[bot]' }}
     steps:
       - run: echo "This DCO job runs on merge_queue event and doesn't check PR contents"

.github/workflows/labeler.yml

@@ -7,7 +7,7 @@ jobs:
     permissions:
       contents: read
       pull-requests: write
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     steps:
       - name: Labeler
         # XXX: !!! SECURITY WARNING !!!

.github/workflows/release-notes-check.yml

@@ -16,7 +16,7 @@ on:
 jobs:
   check-release-notes:
     name: Check release notes are updated
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-slim
     permissions:
       pull-requests: read
     steps: