chore(deps): update postgres docker digest to 4aabea7

Author: renovate[bot]

.github/workflows/test-charmed-dns-policy.yaml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
     services:
       postgres:
-        image: postgres@sha256:8ff36f3c66371cba71d20ceedccfc3de9669a68737607888c4ef0af93abe8e39
+        image: postgres@sha256:4aabea78cf39b90e834caf3af7d602a18565f6fe2508705c8d01aa63245c2e20
         env:
           POSTGRES_PASSWORD: testpassword
         # Set health checks to wait until postgres has started