set up sbt

Author: Atry

.github/workflows/gh-pages.yml

@@ -31,6 +31,7 @@ jobs:
     - uses: actions/setup-node@v1
       with:
         node-version: "${{ steps.nodenv.outputs.node-version }}"
+    - uses: sbt/setup-sbt@v1
     - name: Cache SBT
       uses: actions/cache@v3
       with: