ci: drop manual eggs installation

.gitea/workflows/build.yaml

@@ -57,20 +57,9 @@ jobs:
           hash -r
           csc -version
 
-      - name: Install eggs
-        run: |
-          set -eu
-          mkdir -p .eggs
-          repo="$(chicken-install -repository)"
-          echo "CHICKEN_INSTALL_REPOSITORY=${PWD}/.eggs" >> "$GITHUB_ENV"
-          echo "CHICKEN_REPOSITORY_PATH=${PWD}/.eggs:${repo}" >> "$GITHUB_ENV"
-          export CHICKEN_INSTALL_REPOSITORY="${PWD}/.eggs"
-          export CHICKEN_REPOSITORY_PATH="${PWD}/.eggs:${repo}"
-          # shellcheck disable=SC2046
-          chicken-install $(cat dependencies.txt)
-
+      # Eggs are pinned in eggs.lock and installed by the Makefile into .eggs/.
       - name: Build sexc
-        run: make sexc && ./sexc --help
+        run: make && ./sexc --help
 
       - name: Run tests
-        run: make run-tests
+        run: make check