Update coursier/cache-action requirement to v6

Updates the requirements on [coursier/cache-action](https://github.com/coursier/cache-action) to permit the latest version.
- [Release notes](https://github.com/coursier/cache-action/releases)
- [Commits](https://github.com/coursier/cache-action/commits/730a6a454f386fff4be026f3e304ee7fe68912ac)

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -33,7 +33,7 @@ jobs:
       - uses: olafurpg/setup-scala@v10
         with:
           java-version: "adopt@1.8"
-      - uses: coursier/cache-action@v5
+      - uses: coursier/cache-action@v6
       - run: sbt -v lint
       - name: clean up
         run: "${GITHUB_WORKSPACE}/.github/clean-up.sh"

.github/workflows/release.yml

@@ -24,7 +24,7 @@ jobs:
       - uses: olafurpg/setup-scala@v10
         with:
           java-version: ${{ matrix.jdk }}
-      - uses: coursier/cache-action@v5
+      - uses: coursier/cache-action@v6
       - run: sbt -v ++${{ matrix.scala }} test
       - name: clean up
         run: "${GITHUB_WORKSPACE}/.github/clean-up.sh"