chore(Analysis/InnerProductSpace/Coalgebra): generalize from NormedRing to Ring

[themathqueen]

I forgot to update the hypotheses when I changed it to LinearEquiv from LinearIsometryEquiv.

I also removed the TODO since I'm not convinced we should have them all on one type anymore. For example we have the algebra instances on n -> R and the Hilbert space on EuclideanSpace. Even though we could technically introduce the algebra instances on this Hilbert space, we probably shouldn't be doing that.

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[github-actions]

PR summary cb6b2796fb

Import changes for modified files

No significant changes to the import graph

Import changes for all files

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Declarations diff

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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).