Update actions/cache action to v2

Author: renovate-bot

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
         with:
           node-version: 12
       - name: Cache node modules
-        uses: actions/cache@v1
+        uses: actions/cache@v2
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
@@ -31,7 +31,7 @@ jobs:
         with:
           node-version: 12
       - name: Cache node modules
-        uses: actions/cache@v1
+        uses: actions/cache@v2
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
@@ -50,7 +50,7 @@ jobs:
         with:
           node-version: 12
       - name: Cache node modules
-        uses: actions/cache@v1
+        uses: actions/cache@v2
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
@@ -72,7 +72,7 @@ jobs:
         with:
           node-version: 12
       - name: Cache node modules
-        uses: actions/cache@v1
+        uses: actions/cache@v2
         with:
           path: ~/.npm
           key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}