Give maintainers the ability to provide reason for yanking

[di]

PEP 592 permits the use of an arbitrary string which gives a reason for yanking:

The value of the data-yanked attribute, if present, is an arbitrary string that represents the reason for why the file has been yanked. Tools that process the simple repository API MAY surface this string to end users.

PyPI does not currently support this. Completing this issue would include a UI to allow the user to set this when yanking, an update to the DB model to change this from a boolean to a text field, and an update to the simple page to surface this value if present.

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[pradyunsg]

FYI: pip prints the reason for yanking if it is provided, and if it is not, it prints "Reason for being yanked: <none given>".

As a result of this, any yanked releases on PyPI today will result in pip's output when installing a yanked release saying "Reason for being yanked: <none given>".

Reported/mentioned in pypa/pip#8160 (comment).

[deveshks]

Just to confirm, is this issue also taken up by someone to work on as per #7886 (comment) ?

[daneah]

@deveshks yep, I'm working on this.