refactor(InMemorySinger) - Implement a InMemorySigner::test method

[wacban]

Description

There is a prevalent pattern in our test code:

            InMemorySigner::from_seed(account_id.clone(), KeyType::ED25519, account_id.as_ref());

It's quite verbose and annoying. The goal of this task is to implement a shorter InMemorySigner::test(account_id) that would do the above. Additionally please refactor a few usages of the old pattern with the new, shorter one. It should only be used in tests.

[mkamonMdt]

Hi,
It seems to me that there already is something similar in near-primitives::test_utils called create_user_test_signer.

The above is used already in couple places.

Did you consider using it instead of creating new one? Also maybe returning Singer instead of InMemorySigner could come handy as it would simply #12472 for #1531. What do you think? I could implement that :)

[wacban]

free function

I'm against this though it's more of a preference than objective thing. My thinking is that as developer whenever I need to pass an InMemorySigner somewhere I can just look at that class and use the test method.

Signer

Hmm I would rather return the InMemorySigner but perhaps we can do both? e.g. test returning Self and test_signer returning Signer

I could implement that :)

Feel free to grab this task, thank you!

[mkamonMdt]

@wacban I could provide a followup commit with some more code refactor to use test/test_signer. Please let me know if you would like me to do it :)

[wacban]

@mkamonMdt That would be great, go for it, thank you!