🦺[Tech Debt]: Refactor placement of Tests structure

[kcw-grunt]

Describe the work to be done

per @andhikayuana recommendations: #273 (comment)

since this is not UI test, we can move it to app/src/test instead of app/src/androidTest and using JUnit with mockk.
probably I will help to setup the testing stuff on the next PR

Steps to complete

• Move Constants to the directory
• Open Draft PR and invite comment from @andhikayuana @kcw-grunt
• Move more in the same location when agreed
• Convert to PR and request review (which should be quick approved)