refactor: generalize results about LinearIndependent to Semiring

[eric-wieser]

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[github-actions]

PR summary 7a8bb62fef

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

+ Fintype.linearIndependent_iff_injective
+ LinearIndependent.map_of_injective_injective'

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

[alreadydone]

Oh, I wasn't aware of this PR until I searched GitHub in an attempt to find #18426 moments ago. I just opened #20480 to generalize all generalizable results to semirings (except I didn't examine the DivisionRing section carefully).