test: diff of declarations in lean

[adomani]

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[github-actions]

PR summary 8872c4c0be

Import changes

No significant changes to the import graph

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Declarations diff

+ listDeclsCore

You can run this locally as follows

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

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

[github-actions]

Lean declaration difference 8872c4c0be

Declarations only in 50df960
Mathlib.Meta.Another.eval_expr

Declarations only in 92377b4
Mathlib.Meta.eval_expr