chore: added basic jest testing support

also added an example test for the counter in the components.tsx file to demonstrate functionality of testing configuration. installed all dependencies for testing using --save-dev to make sure they are stored as dev dependencies

ref: N25B-212

tsconfig.app.json

@@ -24,5 +24,5 @@
     "noFallthroughCasesInSwitch": true,
     "noUncheckedSideEffectImports": true
   },
-  "include": ["src"]
+  "include": ["src","test"]
 }