chore(deps): update actions/cache action to v2 (#71)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

Author: renovate[bot]

.github/workflows/build.yml

@@ -25,7 +25,7 @@ jobs:
         id: yarn-cache
         run: echo "::set-output name=dir::$(yarn cache dir)"
 
-      - uses: actions/cache@v1
+      - uses: actions/cache@v2
         with:
           path: ${{ steps.yarn-cache.outputs.dir }}
           key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}
@@ -61,7 +61,7 @@ jobs:
         id: yarn-cache
         run: echo "::set-output name=dir::$(yarn cache dir)"
 
-      - uses: actions/cache@v1
+      - uses: actions/cache@v2
         with:
           path: ${{ steps.yarn-cache.outputs.dir }}
           key: ${{ runner.os }}-yarn-${{ hashFiles('**/yarn.lock') }}