chore(deps): pin dependencies (#484)

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

Author: renovate[bot]

.github/workflows/housekeeping.yaml

@@ -15,11 +15,11 @@ jobs:
       group: cleanup-images
     steps:
       - name: Delete untagged images
-        uses: dataaxiom/ghcr-cleanup-action@v1
+        uses: dataaxiom/ghcr-cleanup-action@cd0cdb900b5dbf3a6f2cc869f0dbb0b8211f50c4 # v1
         with:
           keep-n-untagged: 10
       - name: Delete old release candidate images
-        uses: dataaxiom/ghcr-cleanup-action@v1
+        uses: dataaxiom/ghcr-cleanup-action@cd0cdb900b5dbf3a6f2cc869f0dbb0b8211f50c4 # v1
         with:
           delete-tags: '*-rc*'
           keep-n-tagged: 3

.github/workflows/test.yaml

@@ -39,7 +39,7 @@ jobs:
     timeout-minutes: 10
     services:
       squid-proxy:
-        image: ubuntu/squid:latest
+        image: ubuntu/squid:latest@sha256:98f98aaa024e4a58433450f8adde48ef5748f1ae05133b2367d64317cc881a3a
         ports:
           - 3128:3128