chore(Algebra/CharP/Defs): do not import Field

[YaelDillies]

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[github-actions]

PR summary cb868581fb

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.Algebra.CharP.Defs	420	398	-22 (-5.24%)
Mathlib.Algebra.CharP.Invertible	421	405	-16 (-3.80%)

Import changes for all files

Files	Import difference
Mathlib.Algebra.CharP.Basic Mathlib.Algebra.CharP.Defs	-22
Mathlib.Data.Matrix.CharP Mathlib.Algebra.CharP.Pi	-21
Mathlib.Algebra.CharP.Invertible	-16
3 files Mathlib.Combinatorics.Additive.AP.Three.Defs Mathlib.Combinatorics.Additive.FreimanHom Mathlib.Combinatorics.Additive.Corner.Defs	-10

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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
4817	-1	porting notes

Current commit cb868581fb
Reference commit af8eed890c

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).