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[sergeibbb]

#3788

Description

Checklist

• I have followed the guidelines in the Contributing document
• My changes follow the coding style of this project
• My changes build without any errors or warnings
• My changes have been formatted and linted
• My changes include any required corresponding changes to the documentation (including CHANGELOG.md and README.md)
• My changes have been rebased and squashed to the minimal number (typically 1) of relevant commits
• My changes have a descriptive commit message with a short title, including a Fixes $XXX - or Closes #XXX - prefix to auto-close the issue that your PR addresses

[sergeibbb]

@axosoft-ramint

In the last commit I'm grouping detected PR-identity by providers, because thought that if we know that an URL matches to a GitLab then no need to search for it in GitHub. But if it looks too compicated, then then last commit can be rejected.