Show loading button after internal balance withdrawn

[Ayse-AK]

1. After the user withdraws her MYSTs from the internal balance, the loading button is shown for 1 minute instead of the Withdraw button. The withdraw button is no longer displayed.
2. Replace the note with "Your MYSTs are being transferred..."

[lusine-h]

tested, works as expected

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This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale[bot]]

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