feat: Adding the numel, __getnewargs__ and __concat__ methods to the Shape class

[fnhirwa]

PR Description

This PR adds numel, __getnewargs__ and __concat__ methods to the Shape class and implemented the unit tests.

Related Issue

part of #28617

close #28654
close #28655
close #28656

Checklist

• Did you add a function?
• Did you add the tests?
• Did you run your tests and are your tests passing?
• Did pre-commit not fail on any check?
• Did you follow the steps we provided?

Socials

[Ishticode]

Hi @fnhirwa Hoping you are doing well
Great stuff. Thank you very much for you continuous efforts and contributions. Looks good. I've linked three related issues and this looks good to merge. :)