chore(deps): update docker/setup-buildx-action digest to 2a81c53 (#143)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker/setup-buildx-action | action | digest | `95cefc3` -> `2a81c53`
|

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.github/workflows/creatorsgarten-wiki-cicd.yml

@@ -30,7 +30,7 @@ jobs:
 
       # Workaround: https://github.com/docker/build-push-action/issues/461
       - name: Setup Docker buildx
-        uses: docker/setup-buildx-action@95cefc3c57c7e2ae63996b332541b8a2808e4348
+        uses: docker/setup-buildx-action@2a81c53912fc7ca31856d300b1f878a8e43178dd
 
       # Login against a Docker registry except on PR
       # https://github.com/docker/login-action