Update dependency ts-jest to v26.5.6

Author: renovate-bot

backend/package.json

@@ -64,7 +64,7 @@
     "prettier": "2.2.1",
     "supertest": "6.1.3",
     "swagger-parser": "10.0.2",
-    "ts-jest": "26.5.5",
+    "ts-jest": "26.5.6",
     "ts-loader": "8.1.0",
     "ts-node": "9.1.1",
     "tsconfig-paths": "3.9.0",

backend/yarn.lock

@@ -5731,10 +5731,10 @@ tree-kill@1.2.2:
   resolved "https://registry.yarnpkg.com/tree-kill/-/tree-kill-1.2.2.tgz#4ca09a9092c88b73a7cdc5e8a01b507b0790a0cc"
   integrity sha512-L0Orpi8qGpRG//Nd+H90vFB+3iHnue1zSSGmNOOCh1GLJ7rUKVwV2HvijphGQS2UmhUZewS9VgvxYIdgr+fG1A==
 
-ts-jest@26.5.5:
-  version "26.5.5"
-  resolved "https://registry.yarnpkg.com/ts-jest/-/ts-jest-26.5.5.tgz#e40481b6ee4dd162626ba481a2be05fa57160ea5"
-  integrity sha512-7tP4m+silwt1NHqzNRAPjW1BswnAhopTdc2K3HEkRZjF0ZG2F/e/ypVH0xiZIMfItFtD3CX0XFbwPzp9fIEUVg==
+ts-jest@26.5.6:
+  version "26.5.6"
+  resolved "https://registry.yarnpkg.com/ts-jest/-/ts-jest-26.5.6.tgz#c32e0746425274e1dfe333f43cd3c800e014ec35"
+  integrity sha512-rua+rCP8DxpA8b4DQD/6X2HQS8Zy/xzViVYfEs2OQu68tkCuKLV0Md8pmX55+W24uRIyAsf/BajRfxOs+R2MKA==
   dependencies:
     bs-logger "0.x"
     buffer-from "1.x"