github-actions(deps): bump actions/cache from 2.1.4 to 2.1.6

Bumps [actions/cache](https://github.com/actions/cache) from 2.1.4 to 2.1.6.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](actions/cache@v2.1.4...v2.1.6)

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

.github/workflows/integrate.yaml

@@ -50,7 +50,7 @@ jobs:
         uses: "./.github/actions/composer/composer/determine-cache-directory"
 
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v2.1.4"
+        uses: "actions/cache@v2.1.6"
         with:
           path: "${{ env.COMPOSER_CACHE_DIR }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('composer.lock') }}"
@@ -68,7 +68,7 @@ jobs:
         run: "mkdir -p .build/php-cs-fixer"
 
       - name: "Cache cache directory for friendsofphp/php-cs-fixer"
-        uses: "actions/cache@v2.1.4"
+        uses: "actions/cache@v2.1.6"
         with:
           path: ".build/php-cs-fixer"
           key: "php-${{ matrix.php-version }}-php-cs-fixer-${{ github.sha }}"
@@ -113,7 +113,7 @@ jobs:
         uses: "./.github/actions/composer/composer/determine-cache-directory"
 
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v2.1.4"
+        uses: "actions/cache@v2.1.6"
         with:
           path: "${{ env.COMPOSER_CACHE_DIR }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('composer.lock') }}"
@@ -131,7 +131,7 @@ jobs:
         run: "mkdir -p .build/phpstan"
 
       - name: "Cache cache directory for phpstan/phpstan"
-        uses: "actions/cache@v2.1.4"
+        uses: "actions/cache@v2.1.6"
         with:
           path: ".build/phpstan"
           key: "php-${{ matrix.php-version }}-phpstan-${{ github.sha }}"
@@ -183,7 +183,7 @@ jobs:
         uses: "./.github/actions/composer/composer/determine-cache-directory"
 
       - name: "Cache dependencies installed with composer"
-        uses: "actions/cache@v2.1.4"
+        uses: "actions/cache@v2.1.6"
         with:
           path: "${{ env.COMPOSER_CACHE_DIR }}"
           key: "php-${{ matrix.php-version }}-composer-${{ matrix.dependencies }}-${{ hashFiles('composer.lock') }}"