CATROID-1429 Remove keyboard when no input is possible in upload

[friendo97]

When uploading a project, after entering names&credits a dialog is shown for choosing categories. The softkeyboard is not closed when the dialog pops up. This issue is fixed with this ticket.

Also I refactored a Testclass from Java to Kotlin.

https://jira.catrob.at/browse/CATROID-1429

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[Piki2000]

Good job!

[dandrawes]

Thank you!