Update README - include other NPM scripts

[ghost]

• I've checked that this isn't a duplicate issue.

Update the README to include other scripts like build and test.
For example, the test script should be run to test code. If this is explicitly stated in the DOCs, it will help prevent contributors from submitting PRs with lots of failing tests.

[FarhiaM]

Hi, I would like to work on this 😊

[vikaspotluri123]

I think this will be covered in #76 /cc @aslafy-z

[aslafy-z]

Might be covered by #398 also. I think we have to sync on that point. Maybe wait for it to be merged and then I'll complete it.

[maybebored]

Might be covered by #398 also. I think we have to sync on that point. Maybe wait for it to be merged and then I'll complete it.

@aslafy-z Assign this to me, once #398 is merged. I'll update the readme to resolve this issue and also add a link to ARCHITECTURE.md from #398.

[aslafy-z]

Done @maybebored!