Sidestep the GitHub cache

Author: Svetlitski

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
       - uses: actions/cache@v4
         with:
           path: ~/.opam
-          key: ${{ matrix.os }}-opam-${{ matrix.ocaml-version }}
+          key: ${{ matrix.os }}-opam-${{ matrix.ocaml-version }}-1
 
       - name: Install musl-compatible kernel headers
         run: |