fix(manager/pre-commit): remove category

[RahulGautamSingh]

Changes

• Remove the category field from pre-commit manager as the manager can be used for multiple languages, hence one language as category is misleading

Context

• Ref: Grouping error with zizmor-pre-commit #44958

Please select one of the following:

• This closes an existing Issue, Closes: #
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Please select one option and, if yes, briefly describe how AI was used (e.g., code, tests, docs) and which tool(s) you used.

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Documentation (please check one with an [x])

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The public repository: n/a