feat(AlgebraicGeometry/Birational/RationalMap): add RationalMap.representative

[justus-springer]

Split off from #39317

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[github-actions]

PR summary 1038f55b36

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

+ PartialMap.representative_toRationalMap_equiv
+ RationalMap.representative
+ RationalMap.toRationalMap_representative

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.

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No changes to strong technical debt.

No changes to weak technical debt.

[chrisflav]

There was no need to make this a separate PR, but anyway: Thanks!

maintainer merge

[github-actions]

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