update packages

package.json

@@ -3,9 +3,9 @@
         "test": "jest"
     },
     "devDependencies": {
-        "@types/jest": "^25.1.3",
-        "jest": "^25.1.0",
-        "ts-jest": "^25.2.1",
-        "typescript": "^3.8.2"
+        "@types/jest": "^26.0.14",
+        "jest": "^26.5.3",
+        "ts-jest": "^26.4.1",
+        "typescript": "^4.0.3"
     }
 }