chore: bump coursier/cache-action from 3 to 6

Bumps [coursier/cache-action](https://github.com/coursier/cache-action) from 3 to 6.
- [Release notes](https://github.com/coursier/cache-action/releases)
- [Commits](coursier/cache-action@v3...v6)

---
updated-dependencies:
- dependency-name: coursier/cache-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -19,7 +19,7 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - uses: coursier/cache-action@v3
+    - uses: coursier/cache-action@v6
     - name: Set up JDK 1.8
       uses: actions/setup-java@v1
       with:
@@ -37,7 +37,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@v2
-      - uses: coursier/cache-action@v3
+      - uses: coursier/cache-action@v6
       - name: Set up JDK 1.8
         uses: actions/setup-java@v1
         with: