feat(LocalField): instance Finite (𝒪[K] ⧸ 𝓂[K] ^ n)

[WenrongZou]

For a nonarchimedean local field K, we prove an instance Finite (𝒪[K] ⧸ 𝓂[K] ^ n).

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[github-actions]

PR summary c9e316d330

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.NumberTheory.LocalField.Basic	2219	2221	+2 (+0.09%)

Import changes for all files

Files	Import difference
Mathlib.NumberTheory.LocalField.Basic	2

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Declarations diff (regex)

+ instance (n : ℕ) : Finite (𝒪[K] ⧸ 𝓂[K] ^ n)

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 -- unavailable)

⚠️ No declarations diff yet: there is no built master snapshot at this PR's merge-base (typically a bors-batch intermediate that CI never built). Merge master into this PR and push to refresh.

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No changes to strong technical debt.

No changes to weak technical debt.

Current commit c9e316d330
Reference commit 1f29011071

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).