ci: force use of a new cache on GitHub Actions

The current cache has corrupt data.

Author: djcsdy

.github/workflows/ci.yml

@@ -22,7 +22,7 @@ jobs:
         uses: actions/cache@v2
         with:
           path: ${{steps.find-yarn-cache.outputs.dir}}
-          key: ${{runner.os}}-node${{matrix.node-version}}-yarn-${{hashFiles('**/yarn.lock')}}
+          key: v2-${{runner.os}}-node${{matrix.node-version}}-yarn-${{hashFiles('**/yarn.lock')}}
           restore-keys: ${{runner.os}}-node${{matrix.node-version}}-yarn-
       - name: Set up Node.js v${{matrix.node-version}}
         uses: actions/setup-node@v2
@@ -45,7 +45,7 @@ jobs:
         uses: actions/cache@v2
         with:
           path: ${{steps.find-yarn-cache.outputs.dir}}
-          key: ${{runner.os}}-node${{env.DEPLOY_NODE_VERSION}}-yarn-${{hashFiles('**/yarn.lock')}}
+          key: v2-${{runner.os}}-node${{env.DEPLOY_NODE_VERSION}}-yarn-${{hashFiles('**/yarn.lock')}}
           restore-keys: ${{runner.os}}-node${{env.DEPLOY_NODE_VERSION}}-yarn-
       - name: Set up Node.js
         uses: actions/setup-node@v2