Add make test

Author: hasufell

.github/workflows/test-ghcup.yaml

@@ -87,7 +87,6 @@ jobs:
       - run: which cabal
       - run: cabal --version
 
-
   vanilla-channel:
     strategy:
       matrix:
@@ -163,3 +162,15 @@ jobs:
         run: |
           cat $(stack path --stack-root)/hooks/ghc-install.sh
         shell: bash
+
+  make:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - run: |
+          set -eux
+          pushd ghcup
+          npx bun install
+          popd
+          BUN="npx bun" make -C ghcup
+          git diff --exit-code