Install eli-tester using pkg install

Author: soegaard

.github/workflows/tests.yaml

@@ -15,8 +15,8 @@ jobs:
           variant: CS
           version: current
       - uses: actions/checkout@master
+      - run: sudo raco pkg install eli-tester
       - run: sudo raco pkg update --no-setup --name math-lib --link --batch --auto math-lib/
       - run: sudo raco setup math
-      - run: sudo raco pkg update --no-setup --name eli-tester --link --batch --auto eli-tester/
       - run: sudo raco pkg install --link --batch --auto math-test/
       - run: raco test --drdr math-test/