⬆️ Updates ubuntu to v24

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/backport.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   backport:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-24.04
     name: Backport
     steps:
       - name: Backport

.github/workflows/closing.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   issueClosed:
-    runs-on: ubuntu-18.04
+    runs-on: ubuntu-24.04
     steps:
       - name: Add closed question comment
         uses: peter-evans/create-or-update-comment@v1

.github/workflows/set-milestone-on-pr.yml

@@ -8,7 +8,7 @@ on:
 jobs:
   set-milestone:
     if: github.event.pull_request.merged == true
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-24.04
     steps:
       - name: Checkout code
         uses: actions/checkout@v2