feat(LinearAlgebra): rank of commutative semiring over itself

[alreadydone]

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[github-actions]

PR summary 760a178da4

Import changes for modified files

Dependency changes

File	Base Count	Head Count	Change
Mathlib.LinearAlgebra.Dimension.Basic	778	780	+2 (+0.26%)
Mathlib.LinearAlgebra.Dimension.Subsingleton	779	781	+2 (+0.26%)
Mathlib.LinearAlgebra.Dimension.Finrank	780	782	+2 (+0.26%)
M scripts/count-trans-deps.py
M scripts/count-trans-deps.py
M scripts/count-trans-deps.py

Import changes for all files

Files	Import difference
3 files Mathlib.LinearAlgebra.Dimension.Basic Mathlib.LinearAlgebra.Dimension.Finrank Mathlib.LinearAlgebra.Dimension.Subsingleton	2

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Declarations diff

+ CommSemiring.finrank_self
+ CommSemiring.rank_self
+ Module.one_le_rank_iff
+ exists_finset_eq_card
+ le_rank_iff
+ le_rank_iff_exists_finset
+ le_rank_iff_exists_linearMap

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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No changes to technical debt.

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).