Add "latest" tag when building release

.github/workflows/build.yml

@@ -97,6 +97,9 @@ jobs:
     name: Combine Docker Images
     runs-on: ubuntu-20.04
     if: github.event_name != 'pull_request' && github.repository == 'photoview/photoview'
+    defaults:
+      run:
+        shell: bash
 
     needs: [build]
 
@@ -122,7 +125,7 @@ jobs:
           if [[ $VERSION =~ ^(([0-9]{1,3})\.[0-9]{1,3})\.[0-9]{1,3}$ ]]; then
             VERSION_MINOR=${BASH_REMATCH[1]}
             VERSION_MAJOR=${BASH_REMATCH[2]}
-            TAGS+=("${VERSION_MAJOR}" "${VERSION_MINOR}")
+            TAGS+=("${VERSION_MAJOR}" "${VERSION_MINOR}" "latest")
           fi
 
           for TAG in ${TAGS[*]}; do