Transfer copyright to Scala Center

.github/workflows/cla.yml

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+name: Scala CLA
+on: [pull_request]
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - name: Check CLA
+      env:
+        AUTHOR: ${{ github.event.pull_request.user.login }}
+      run: |
+        echo "Pull request submitted by $AUTHOR";
+        signed=$(curl -s "https://www.lightbend.com/contribute/cla/scala/check/$AUTHOR" | jq -r ".signed");
+        if [ "$signed" = "true" ] ; then
+          echo "CLA check for $AUTHOR successful";
+        else
+          echo "CLA check for $AUTHOR failed";
+          echo "Please sign the Scala CLA to contribute to the Scala compiler.";
+          echo "Go to https://www.lightbend.com/contribute/cla/scala and then";
+          echo "comment on the pull request to ask for a new check.";
+          echo "";
+          echo "Check if CLA is signed: https://www.lightbend.com/contribute/cla/scala/check/$AUTHOR";
+          exit 1;
+        fi;