AccountActivity: animate progress bar becoming invisible (bitfireAT/davx5#366)

* [WIP] Animate invisibility

* Reordered for cleaner look

Signed-off-by: Arnau Mora <arnyminerz@proton.me>

* Fixed animation

Signed-off-by: Arnau Mora <arnyminerz@proton.me>

* Reduced animation time for going to visible to 0

Signed-off-by: Arnau Mora <arnyminerz@proton.me>

* Remove logging

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Signed-off-by: Arnau Mora <arnyminerz@proton.me>
Co-authored-by: Arnau Mora <arnyminerz@proton.me>