ci(jest): use --ci --maxWorkers=50%

Author: chimurai

.github/workflows/ci.yml

@@ -118,7 +118,7 @@ jobs:
         run: yarn install --frozen-lockfile --ignore-scripts
 
       - name: yarn test
-        run: yarn test --ci --reporters="default" --reporters="github-actions"
+        run: yarn test --ci --maxWorkers=50% --reporters="default" --reporters="github-actions"
 
         env:
           CI: true
@@ -148,7 +148,7 @@ jobs:
         run: yarn install --frozen-lockfile --ignore-scripts
 
       - name: yarn coverage
-        run: yarn coverage
+        run: yarn coverage --ci --maxWorkers=50%
 
       - name: Coveralls
         uses: coverallsapp/github-action@master