[Merged by Bors] - chore: reduce open Fin.NatCast

[Komyyy]

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[github-actions]

PR summary 0ad288bf4a

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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Decrease in tech debt: (relative, absolute) = (1.00, 0.07)

Current number	Change	Type
14	-1	NatCast (Fin n) instances

Current commit 90e08565a4
Reference commit 0ad288bf4a

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).

[eric-wieser]

bors d+

Thanks!

[mathlib-bors]

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

[Komyyy]

bors r+

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

• CI Success