Use runner context in cache yml

README.md

@@ -187,20 +187,23 @@ You can persist composer's internal cache directory using the [`action/cache`](h
 - name: Get Composer Cache Directory
   id: composer-cache
   run: echo "::set-output name=dir::$(composer config cache-files-dir)"
+
 - name: Cache on linux and macOS
-  if: matrix.operating-system != 'windows-latest'
+  if: runner.os != 'Windows'
   uses: actions/cache@v1
   with:
     path: ${{ steps.composer-cache.outputs.dir }}
     key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
     restore-keys: ${{ runner.os }}-composer-
+
 - name: Cache on windows
-  if: matrix.operating-system == 'windows-latest'
+  if: runner.os == 'Windows'
   uses: actions/cache@v1
   with:
     path: ${{ steps.composer-cache.outputs.dir }}
     key: ${{ runner.os }}-composer-${{ hashFiles('**composer.lock') }}
     restore-keys: ${{ runner.os }}-composer-
+
 - name: Install Dependencies
   run: composer install --prefer-dist
 ```