Bump actions/cache from v2 to v2.1.4 (#75)

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>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
diff --git a/.github/workflows/maven.yml b/.github/workflows/maven.yml
index b5a0f0f..b3f1244 100644
--- a/.github/workflows/maven.yml
+++ b/.github/workflows/maven.yml
@@ -34,7 +34,7 @@
         
     steps:
     - uses: actions/checkout@v2.3.4
-    - uses: actions/cache@v2
+    - uses: actions/cache@v2.1.4
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}