Migrate to vitest

This MR migrates the tests to vitest.

I think this migration is benifitial for us because of the following reasons:

• vitest is faster than jest
• vitest has typescript support out of the box (should resolve issues with weird code coverage)
• the GEMIMEG-Tool will use vite aswell at some point in the future (because of Vue 3 and Nuxt)

See https://vitest.dev/guide/comparisons.html

tests/DCC/GP_DCC_Temperature_Simplified/AdministrativeData.CalibrationLaboratory.test.ts

 /**
- * @jest-environment ./tests/XMLEnvironment.ts
- * @xml ./tests/resources/GP_Temperature_Simplified.xml
+ * @vitest-environment-options { "xmlPath": "./tests/resources/GP_Temperature_Simplified.xml" }
  */
 
 import { select, toTextArr, toTextContentArr } from "../../util";
@@ -26,7 +25,7 @@ describe("GP_DCC_Temperature_Simplified: CalibrationLaboratoryType", () => {
   let dcc: DCCDocument, calibrationLaboratory: CalibrationLaboratoryType, dom;
 
   beforeEach(() => {
-    ({ dcc, dom } = xmlEnv.recreateEnv());
+    ({ dcc, dom } = recreateEnv());
     calibrationLaboratory = dcc.digitalCalibrationCertificate.administrativeData.calibrationLaboratory;
   });