[native] Added show/hide password button.

Summary:
Linear issue: https://linear.app/comm/issue/ENG-2050/add-see-password-button-on-the-login-page-and-dont-clear-text-inputs
I've added show/hide password button on tight side of password input in login screen.
I've added new component PasswordInput wrapping regular TextInput.
In PasswordInput I used stateto keep track of button state.
Question:
Should we clear username and password after unsuccessful login?
If we have "show password" as an option I don't think it's necessary, but it's up to you.

Test Plan:
Built app.
Tested native app in simulators, both iOS and Android.

Reviewers: tomek, atul, marcin, kamil, ginsu

Reviewed By: tomek, kamil

Subscribers: abosh, kamil, marcin, atul, tomek, ashoat

Differential Revision: https://phab.comm.dev/D5489