build(deps): bump docker/build-push-action from 2 to 2.4.0 (#1010)

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 2 to 2.4.0.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v2...v2.4.0)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/docker.yml

@@ -18,7 +18,7 @@ jobs:
       with:
         username: kjconroy
         password: ${{ secrets.DOCKER_PASSWORD }}
-    - uses: docker/build-push-action@v2
+    - uses: docker/build-push-action@v2.4.0
       with:
         context: .
         file: ./Dockerfile