[Merged by Bors] - chore(Data/Fin/Basic): split off rev lemmas

[BoltonBailey]

This PR splits out lemmas about the Fin.rev function from Data.Fin.Basic. This addresses an instance of a long file linter trigger.

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[github-actions]

PR summary b0b660667c

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
There are 3919 files with changed transitive imports taking up over 170246 characters: this is too many to display!
You can run scripts/import_trans_difference.sh all locally to see the whole output.

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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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Decrease in tech debt: (relative, absolute) = (1.00, 0.02)

Current number	Change	Type
58	-1	large files

Current commit b0b660667c
Reference commit 3c8e6314aa

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).

[Ruben-VandeVelde]

This seems reasonable to me

maintainer merge

[github-actions]

🚀 Pull request has been placed on the maintainer queue by Ruben-VandeVelde.

[eric-wieser]

bors d+

Thanks!

[mathlib-bors]

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

[BoltonBailey]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• Build
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