Update docker/setup-buildx-action digest to e468171 (#415)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
|
[docker/setup-buildx-action](https://redirect.github.com/docker/setup-buildx-action)
| action | digest | `18ce135` -> `e468171` |

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Author: lettuce-bot[bot]

.github/workflows/pull-request.yaml

@@ -12,7 +12,7 @@ jobs:
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4
 
       - name: Setup buildx
-        uses: docker/setup-buildx-action@18ce135bb5112fa8ce4ed6c17ab05699d7f3a5e0 # v3
+        uses: docker/setup-buildx-action@e468171a9de216ec08956ac3ada2f0791b6bd435 # v3
 
       - name: Build container image
         uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83 # v6