[5.0] Add proper error handling for public folder cli installation

[HLeithner]

Summary of Changes

PublicFolderGeneratorHelper::createPublicFolder() returns void but throw exception

Testing Instructions

Install with cli and public folder

Actual result BEFORE applying this Pull Request

Execution stops after
Creating the public folder... (no new line)
reason for this is createPublicFolder() returns void which converts to false and ends with Command::FAILURE you Don't get a success message

Expected result AFTER applying this Pull Request

You get a success message after cli installation with public folder.

[dgrammatiko]

I have tested this item ✅ successfully on 0c5a204

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[bembelimen]

I have tested this item ✅ successfully on 0c5a204

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[Quy]

RTC

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[richard67]

Thanks.