Add funding link to pyproject.toml

[stevepiercy]

Closes #800

Also fix link to change log to point to stable, not latest.

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[coveralls]

Pull Request Test Coverage Report for Build 19033967542

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 97.871%

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Totals
Change from base Build 19033946821:	0.0%
Covered Lines:	8154
Relevant Lines:	8323

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💛 - Coveralls