change runners to be ubuntu-latest

Author: hadryyassine

.github/workflows/micronaut.yml

@@ -60,7 +60,7 @@ permissions:
 jobs:
   build-graalvm-and-micronaut:
     name: Native Tests
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
     - name: Checkout oracle/graal
       uses: actions/checkout@v4

.github/workflows/reachability-metadata.yml

@@ -58,7 +58,7 @@ permissions:
 jobs:
   populate-matrix:
     name: Populate matrix
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     outputs:
       matrix: ${{ steps.set-matrix.outputs.matrix }}
     steps: