[393100] Bitbucket server import fix pagination

What does this MR do and why?

Fix for Bitbucket Server Importer only shows 25 repositories. I suspect that it was copy-paste mistake from original dev because parent component is anonymous/root one without any properties to be inherited by $attrs.

Screenshots or screen recordings

Local test

How to set up and validate locally

• Setup bitbucket server locally (I used official docker image)
• Create few repositories for on Bitbucket Server (I tested on 6).
• Change PAGE_LENGTH const in lib/bitbucket_server/paginator.rb to not create 25+ repos instead of few (I tested with 2).
• Open bitbucket server import page and make sure that repos fetched page by page until the end of list.

MR acceptance checklist

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