Update snapshot-branch.yml

.github/workflows/snapshot-branch.yml

@@ -9,6 +9,10 @@ jobs:
     steps:
     - name: 'Checkout'
       uses: actions/checkout@v2
+      with:
+        fetch-depth: 0 # needed to have the tags below
+    - name: 'Ensure git is installed'
+      run: sudo apt-get install -y git
     - name: 'Set up JDK 11'
       uses: actions/setup-java@v1
       with:
@@ -53,6 +57,12 @@ jobs:
         git tag --sort=-creatordate | head -n5
         currenttag=$(git tag --sort=-creatordate | grep -v latest | grep "^v[0-9].*" | head -n1)
         echo "current tag: $currenttag"
+        function join_by {
+          local d=${1-} f=${2-}
+          if shift 2; then
+          printf %s "$f" "${@/#/$d}"
+          fi
+        }
         # tokenize whenever we transition from numbers to whatever else
         # 5.2b4 -> (5 . 2 b 4)
         currentver=${currenttag#?} # remove the v