chore(deps): update vexxhost/docker-atmosphere digest to 9dc904e (#320)

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

Author: renovate[bot]

.github/workflows/build.yml

@@ -25,7 +25,7 @@ jobs:
         with:
           egress-policy: audit
 
-      - uses: vexxhost/docker-atmosphere/.github/actions/build-image@672cf56c8b828e444b6e7906d0ee355c7ec1dea9 # main
+      - uses: vexxhost/docker-atmosphere/.github/actions/build-image@9dc904e06dcde958bf8a0b3230715d32b9e3a85f # main
         with:
           image-name: python-openstackclient
           push: ${{ github.event_name != 'pull_request' }}