Bump actions/cache from v2 to v2.1.4

Bumps [actions/cache](https://github.com/actions/cache) from v2 to v2.1.4.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](https://github.com/actions/cache/compare/v2...26968a09c0ea4f3e233fdddbafd1166051a095f6)
Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/build.yml

@@ -99,7 +99,7 @@ jobs:
       cache-version: v1
     steps:
       - uses: actions/checkout@v2
-      - uses: actions/cache@v2
+      - uses: actions/cache@v2.1.4
         with:
           path: ${{ env.package-dir }}
           key: ${{ runner.os }}-cygwin-${{ env.cache-version }}