feat(plugin-git): improve contributors sorting

[pengzhanbo]

Before submitting the PR, please make sure you do the following

• Read the Contributing Guidelines.
• Provide a description in this PR that addresses what the PR is solving. If this PR is going to solve an existing issue, please reference the issue (e.g. close #123).

What is the purpose of this pull request?

• Bug fix
• New feature
• Other

Description

Since the commits information is sorted starting from the latest, this means that the first contributor obtained from the commits may not necessarily be the original contributor of the file.

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[coveralls]

Pull Request Test Coverage Report for Build 12355157921

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 60.196%

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Totals
Change from base Build 12353692663:	0.0%
Covered Lines:	1308
Relevant Lines:	1969

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💛 - Coveralls