chore(deps): update dependency ts-jest to v26.5.6

Author: renovate-bot

package-lock.json

@@ -36,7 +36,7 @@
     "graphql-codegen": "0.4.0",
     "jest": "26.6.3",
     "standard-version": "9.3.0",
-    "ts-jest": "26.5.5",
+    "ts-jest": "26.5.6",
     "typescript": "4.2.4"
   },
   "author": "Fabio Benedetti"