Update dependency @types/jest to v26.0.15 (#761)

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

Author: renovate[bot]

package-lock.json

@@ -29,7 +29,7 @@
         "@babel/preset-typescript": "7.12.1",
         "@types/eslint-config-prettier": "6.11.0",
         "@types/glob": "7.1.3",
-        "@types/jest": "26.0.14",
+        "@types/jest": "26.0.15",
         "@types/lodash": "4.14.162",
         "@types/minimatch": "3.0.3",
         "@types/node": "12.12.21",