Update dependency jest to v26

Author: renovate-bot

package.json

@@ -66,7 +66,7 @@
     "eslint": "^6.1.0",
     "husky": "^4.2.1",
     "isomorphic-fetch": "^2.2.1",
-    "jest": "^25.1.0",
+    "jest": "^26.0.0",
     "react": "^16.4.0",
     "react-dom": "^16.4.0",
     "react-redux": "^7.1.1",