ci: ccache-action added to ci-conan

.github/workflows/ci-conan.yml

@@ -78,6 +78,11 @@ jobs:
         downcast_mode: [ "on", "auto" ]
     steps:
       - uses: actions/checkout@v2
+      - uses: hendrikmuhs/ccache-action@v1
+        if: runner.os == 'Linux'
+        with:
+          key: ${{ matrix.config.compiler.type }}-${{ matrix.config.compiler.version }}-${{ matrix.build_type }}
+          max-size: 100M
       - name: Install Clang
         if: matrix.config.compiler.type == 'CLANG'
         shell: bash