A sponsor page per project

[felipecrs]

It would be nice if we could have a link such as:

https://github.com/vscode-shellcheck/vscode-shellcheck/sponsor

That would list all the available sponsoring options, just like the homepage of the project shows.

This would be especially useful now that VS Code supports sponsors on extensions, but they only accept one URL to redirect to (while the project can have multiple sponsoring options, or people). Here is one referred discussion.