feat: migrate unit tests to Jest (#6353)

* config(jest): updated setup
* config(jest): update testMatch to include jsx files
* config(jest): add transformIgnorePatterns
* config(jest): update ignore files that do not work in jest yet
* config: add test:unit-jest to test script

* fix(jest): lint with eslint-plugin-jest

* refactor(jest): move unit test directory
* refactor(mocha): restore mocha tests that fail in jest

* docs(jest): update helpful scripts with test:unit-jest

test/unit/swagger-ui-dist-package/absolute-path.js

@@ -0,0 +1,12 @@
+
+import path from "path"
+import getAbsoluteFSPath from "../../../swagger-ui-dist-package/absolute-path"
+
+describe("swagger-ui-dist", function(){
+  describe("getAbsoluteFSPath", function(){
+    it("returns absolute path", function(){
+      const expectedPath = path.resolve(__dirname, "../../../swagger-ui-dist-package")
+      expect(getAbsoluteFSPath()).toEqual(expectedPath)
+    })
+  })
+})