chore(Data/List/Lookmap): remove import all

[thorimur]

This PR removes an unnecessary import all and further minimizes imports in Mathlib.Data.List.Lookmap. Found while exploring uses of import all in mathlib.

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[github-actions]

PR summary 9cfb293306

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Data.List.Lookmap	62	60	-2 (-3.23%)

Import changes for all files

Files	Import difference
Mathlib.Data.List.Lookmap	-2
6 files Mathlib.Data.Finmap Mathlib.Data.Finsupp.AList Mathlib.Data.List.AList Mathlib.Data.List.Sigma Mathlib.SetTheory.Ordinal.CantorNormalForm Mathlib.Testing.Plausible.Functions	-1

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Declarations diff (regex)

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## from your `mathlib4` directory:
git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci

## summary with just the declaration names:
../mathlib-ci/scripts/pr_summary/declarations_diff.sh <optional_commit>

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

The doc-module for scripts/pr_summary/declarations_diff.sh in the mathlib-ci repository contains some details about this script.

Declarations diff (Lean)

✅ Lean-aware diff — post-build, computed from the Lean environment (commit 9cfb293).

• +0 new declarations
• −0 removed declarations

No declaration differences.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit 9cfb293306
Reference commit 4d6f98930f

This script lives in the mathlib-ci repository. To run it locally, from your mathlib4 directory:

git clone https://github.com/leanprover-community/mathlib-ci.git ../mathlib-ci
../mathlib-ci/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).

[github-actions]

✅ PR Title Formatted Correctly

The title of this PR has been updated to match our commit style conventions.
Thank you!

[grunweg]

Thanks!
maintainer delegate

[github-actions]

🚀 Pull request has been placed on the maintainer queue by grunweg.