CI: Support branches for image tags

This allows you to create a branch like `tag/23.10` which will
deploy the image with the tag `23.10`.

.github/workflows/wkdev-sdk.yml

@@ -1,9 +1,10 @@
 name: wkdev-sdk
 on:
   push:
-    branches: [ main ]
+    branches: [ main, tag/** ]
     paths-ignore: [ docs/*, README.md]
   pull_request:
+    branches: [ main, tag/** ]
     paths-ignore: [ docs/*, README.md]
 defaults:
   run:
@@ -16,6 +17,8 @@ jobs:
         run: |
           if [ "${GITHUB_BASE_REF}" = 'main' ]; then
             tag_name='latest'
+          elif [[ "${GITHUB_BASE_REF}" =~ ^tag/(.*)$ ]]; then
+            tag_name="${BASH_REMATCH[1]}"
           else
             tag_name="${GITHUB_BASE_REF}"
           fi
@@ -68,12 +71,14 @@ jobs:
   deploy:
     runs-on: ubuntu-22.04
     needs: build
-    if: github.ref_name == 'main'
+    if: github.ref_name == 'main' || startsWith(github.ref_name, 'tag/')
     steps:
       - name: Set tag name
         run: |
           if [ "${GITHUB_BASE_REF}" = 'main' ]; then
             tag_name='latest'
+          elif [[ "${GITHUB_BASE_REF}" =~ ^tag/(.*)$ ]]; then
+            tag_name="${BASH_REMATCH[1]}"
           else
             tag_name="${GITHUB_BASE_REF}"
           fi