[Merged by Bors] - feat(RingTheory): Algebra.FinitePresentation descends along faithfully flat algebras

[chrisflav]

From Pi1.

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[github-actions]

PR summary 8ca4eacd8c

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference
Mathlib.RingTheory.Finiteness.Descent (new file)	1953

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Declarations diff

+ Algebra.TensorProduct.commRight_symm_tmul
+ Finite.codescendsAlong_faithfullyFlat
+ FinitePresentation.codescendsAlong_faithfullyFlat
+ FinitePresentation.of_finitePresentation_tensorProduct_of_faithfullyFlat
+ FiniteType.codescendsAlong_faithfullyFlat
+ FiniteType.of_finiteType_tensorProduct_of_faithfullyFlat
+ Ideal.FG.of_FG_map_of_faithfullyFlat
+ Module.Finite.of_finite_tensorProduct_of_faithfullyFlat
+ commRight
+ commRight_tmul
+ exists_sum_tmul_eq

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).

[erdOne]

Otherwise LGTM

[erdOne]

Thanks!
maintainer merge

[github-actions]

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

[joelriou]

Thanks!

bors merge

[mathlib-bors]

Pull request successfully merged into master.

Build succeeded:

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