Bump docker/build-push-action from 4 to 6

Bumps [docker/build-push-action](https://github.com/docker/build-push-action) from 4 to 6.
- [Release notes](https://github.com/docker/build-push-action/releases)
- [Commits](docker/build-push-action@v4...v6)

---
updated-dependencies:
- dependency-name: docker/build-push-action
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/build-publish.yml

@@ -24,7 +24,7 @@ jobs:
       -
         name: Build and push - D7
         id: docker_build_7
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./7/
@@ -33,7 +33,7 @@ jobs:
       -
         name: Build and push - D9
         id: docker_build_9
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./9/
@@ -43,7 +43,7 @@ jobs:
       -
         name: Build and push - D10
         id: docker_build_10
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./10/
@@ -53,7 +53,7 @@ jobs:
       -
         name: Build and push - D11
         id: docker_build_11
-        uses: docker/build-push-action@v4
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./11/
@@ -64,7 +64,7 @@ jobs:
       -
         name: Build and push - ContentaCMS
         id: docker_build_contenta
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./contentacms/
@@ -74,7 +74,7 @@ jobs:
       -
         name: Build and push - Thunder
         id: docker_build_thunder
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./thunder/
@@ -84,7 +84,7 @@ jobs:
       -
         name: Build and push - Varbase
         id: docker_build_varbase
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./varbase/
@@ -94,7 +94,7 @@ jobs:
       -
         name: Build and push - govCMS
         id: docker_build_govcms
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         continue-on-error: true
         with:
           context: ./govcms/