[IMPROVEMENT] Adds animation when expanding/collapsing the login options

[hfeky]

@RocketChat/android

Changes:

Added animation when expanding/collapsing login options using ValueAnimator.

Screenshots or GIF for the change:

[CLAassistant]

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[CLAassistant]

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[philipbrito]

Looking really nice @HusseinElFeky! ❤️

[philipbrito]

There are some wrong code formatting here. Please follow our coding style.

[philipbrito]

@divyanshub024 is the dev who really likes playing with animations here. Feel free to review it too @divyanshub024 .

[hfeky]

Thank you @filipedelimabrito! Ah yes, my mistake regarding code formatting. I just usually use Android Studio Format Code shortcut every while and then, and that must have been the reason. I have just adjusted the continuation indent to be 4 right now through Android Studio's settings. Thanks for the heads up!

[philipbrito]

@HusseinElFeky Animations is really looking good, but it is showing wrong (disable) login options for some servers. Could you fix it, please?

[hfeky]

@filipedelimabrito I have fixed incorrect login options showing up for some servers. Please let me know if there is any other issue.

[philipbrito]

It is working like a charm now. Thanks @HusseinElFeky!