Fix issue where sbt is no longer being found during 'sbt assembly' co…

…mmand

Add explicit 'sbt/setup-sbt@v1' action in 'Public Artifacts'
See https://www.scala-sbt.org/1.x/docs/GitHub-Actions-with-sbt.html

.github/workflows/ci.yaml

@@ -58,6 +58,9 @@ jobs:
           distribution: temurin
           java-version: 11.0.19
 
+      - name: Setup sbt launcher
+        uses: sbt/setup-sbt@v1
+
       - name: Configure AWS Credentials
         uses: aws-actions/configure-aws-credentials@v1
         with: