Source model generation for EAV attribute input

[ProkopovVitaliy]

Add possibility to select or generate source model for eav attribute input in the Product attribute setup patch generator dialog.

[m2-assistant]

Hi @ProkopovVitaliy. Thank you for your report.
To help us process this issue please make sure that you provided sufficient information.

Please, add a comment to assign the issue: @magento I am working on this

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[ProkopovVitaliy]

@magento I am working on this