Merge pull request #1165 from alphagov/sengi/release-tagging-robustness

Fetch latest release tag more robustly.

.github/workflows/release.yml

@@ -19,12 +19,13 @@ jobs:
       - name: Find latest version tag
         id: find-last-tag
         run: |
-          git fetch --tags --deepen=100
+          last_tag=$(
+            git ls-remote -q --exit-code --tags --sort=-version:refname origin 'v*' |
+            head -1 | grep -Eo 'v[0-9]+'
+          )
 
-          last_tag=$(git describe --tags --match "v*" --abbrev=0)
-
-          if [ -z "$last_tag" ]; then
-            echo "No previous tag found."
+          if [[ ! "$last_tag" =~ ^v[0-9]*$ ]]; then
+            echo "No valid previous tag found. last_tag=$last_tag"
             exit 1
           fi