Wallet urls methods.

[OmarEMC]

Motivation

In some cases we want the sign in process not to redirect the whole page, but to be open in a popup window.
As mentioned in near#1010

Description

Added to extra methods (requestSignInLink and requestSignInLink) to the WalletConnection, to get the needed urls to the NEAR wallet.

Checklist

• Read the contributing guidelines
• Commit messages follow the conventional commits spec
• Performed a self-review of the PR
• Added automated tests (The methods added are already tested as they are executed by the ones with a writed test)
• Manually tested the change