[Merged by Bors] - chore: fix implicit-reducible diamond in DegLex

[sgouezel]

The following fails on master, works in the PR:

example : (Finsupp.DegLex.instLinearOrderDegLexNat.toLT : LT
(DegLex (α →₀ ℕ))) =
    Finsupp.DegLex.instLTDegLexNat := by
  with_reducible_and_instances rfl

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[github-actions]

PR summary cc26c21489

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/pr_summary/declarations_diff.sh <optional_commit>

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

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

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Decrease in tech debt: (relative, absolute) = (2.00, 0.00)

Current number	Change	Type
6216	-2	backward.isDefEq.respectTransparency

Current commit ddd7efd184
Reference commit cc26c21489

You can run this locally as

./scripts/reporting/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).

[kbuzzard]

Nice!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

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