ci: switch to ubuntu-slim where possible

Author: amezin

.github/workflows/build.yml

@@ -15,7 +15,7 @@ defaults:
 
 jobs:
   setup:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     timeout-minutes: 5
     outputs:
       names: ${{ steps.names.outputs.names }}

.github/workflows/cleanup.yml

@@ -15,7 +15,7 @@ defaults:
 
 jobs:
   setup:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     timeout-minutes: 5
     outputs:
       images: ${{ steps.images.outputs.names }}
@@ -47,7 +47,7 @@ jobs:
 
   image:
     needs: setup
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     timeout-minutes: 15
     strategy:
       fail-fast: false

.github/workflows/release.yml

@@ -15,7 +15,7 @@ defaults:
 
 jobs:
   release:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-slim
     env:
       GH_TOKEN: ${{ github.token }}
       GH_REPO: ${{ github.repository }}