[Merged by Bors] - doc(GroupTheory): fix file refs

[harahu]

Fix some stale documentation file refs.

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[github-actions]

PR summary 51192f7a45

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for script/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

[bryangingechen]

Thanks!
bors r+

[bryangingechen]

bors r-
bors d+

There's a line that's too long: https://github.com/leanprover-community/mathlib4/actions/runs/20522522089/job/58960134164?pr=33305#step:22:36

[mathlib-bors]

✌️ harahu can now approve this pull request. To approve and merge a pull request, simply reply with bors r+. More detailed instructions are available here.

[mathlib-bors]

Canceled.

[harahu]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

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