chore: eta reduce in proofs

[felixpernegger]

Simplify proof by applying eta reduction (i.e. f instead of fun x => f x).

This is purely stylistic.

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[felixpernegger]

!bench

[mathlib-bors]

This pull request is now in draft mode. No active bors state needed cleanup.

While this PR remains draft, bors will ignore commands on this PR. Mark it ready for review before using commands like bors r+ or bors try.

[leanprover-radar]

Benchmark results for 86e6105 against 324e878 are in. No significant results found. @felixpernegger

• 🟥 build//instructions: +146.5G (+0.10%)

Small changes (1🟥)

• 1 hidden

[github-actions]

PR summary 86e6105079

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

---

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 -- pending)

Computed after the build finishes.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit 86e6105079
Reference commit 324e878abc

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).

[felixpernegger]

!bench

[leanprover-radar]

Benchmark results for 86e6105 against 324e878 are in. (These commits have already been benchmarked in a previous command.) No significant results found. @felixpernegger

• 🟥 build//instructions: +146.5G (+0.10%)

Small changes (1🟥)

• 1 hidden