chore(Combinatorics/Enumerative/Partition): auto-derive DecidableEq

[LeoDog896]

Original bug fixed in leanprover/lean4#2918.

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[github-actions]

PR summary 6fa34d72c6

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, 0.00)

Current number	Change	Type
4835	-1	porting notes

Current commit 6fa34d72c6
Reference commit e8a30842b9

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).