chore(deps): update docker/build-push-action digest to cb8fc75 (#9)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker/build-push-action | action | digest | `f2a1d5e` -> `cb8fc75` |

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.github/workflows/publish-backup-tag.yml

@@ -50,7 +50,7 @@ jobs:
 
       - name: Build and push Docker image
         id: push
-        uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
+        uses: docker/build-push-action@cb8fc7586f9ad9441b20c33e0f6e8b1b58d8b4c6
         with:
           context: ./images/backup
           push: true

.github/workflows/publish-tag.yml

@@ -50,7 +50,7 @@ jobs:
 
       - name: Build and push Docker image
         id: push
-        uses: docker/build-push-action@f2a1d5e99d037542a71f64918e516c093c6f3fc4
+        uses: docker/build-push-action@cb8fc7586f9ad9441b20c33e0f6e8b1b58d8b4c6
         with:
           context: ./images/operator
           push: true