Add more tests for Create Image Wizard

- sanity validation of each of the 4 steps
- click through buttons Next/Back/Cancel

Notes:

- add data-testid attribute for the release select field b/c
there's no better way to query it
- add @testing-library/jest-dom for additional asserts

package.json

@@ -43,6 +43,7 @@
     "@babel/preset-react": "^7.8.3",
     "@redhat-cloud-services/frontend-components-config": "1.0.0",
     "@testing-library/react": "^11.0.4",
+    "@testing-library/jest-dom": "^5.10.1",
     "babel-core": "^7.0.0-bridge.0",
     "babel-eslint": "^10.0.3",
     "babel-jest": "^26.1.0",