Update GitHub Actions to use Ubuntu 20.04

Author: x86-39

.github/workflows/galaxy-import.yml

@@ -13,7 +13,7 @@ name: Import to Galaxy
 jobs:
   galaxy-import:
     name: Import to Galaxy
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     if: ${{ github.event.workflow_run.conclusion == 'success' }}
     steps:
       - name: Check out the codebase.

.github/workflows/molecule.yml

@@ -8,7 +8,7 @@ name: CI
 
 jobs:
   molecule:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - name: Checkout
         uses: actions/checkout@v3