DEPR-48 Remove all references to deprecated CourseTalk widget

[sarina]

See https://github.com/edx/edx-platform/pull/25571

No doc ticket

Remove references to CourseTalk widget which was deleted as part of DEPR-48. See the above PR for more detail.

Reviewers

Possible roles follow. The PR submitter checks the boxes after each reviewer finishes and gives 👍.

• Subject matter expert: @marcotuts
• Subject matter expert:
• Doc team review (sanity check, copy edit, or dev edit?): @edx/doc
• Product review:
• Partner support:
• PM review:

FYI: Tag anyone else who might be interested in this PR here.

Testing

• Ran ./run_tests.sh without warnings or errors

HTML Version (optional)

• Build an RTD draft for your branch and add a link here

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Post-review

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• Squash commits

[sarina]

@nedbat I'm not sure how to read the failing test report - any advice?

[nedbat]

The check output is verbose. Because it ended with TOTAL SPHINX WARNINGS: 1, you can search for "WARNINGS: 1" to find the book that had the warning, then scroll up to:

https://github.com/edx/edx-documentation/pull/1921/checks?check_run_id=2008093477#step:6:1111

/home/runner/work/edx-documentation/edx-documentation/en_us/open_edx_release_notes/source/eucalyptus.rst:110:
WARNING: undefined label: installation:add coursetalk (if the link has no caption the label must precede a section header)

A tricky case: the thing you are deleting is referred to by old release notes.

[sarina]

Huh.... removing references from old release notes seems incredibly wrong, I'll try to see what I can to to preserve some of the information, I suppose?

[sarina]

Hrm. @nedbat would it be better to keep the documentation and edit it to indicate it's deprecated, or simply remove the reference from the 2016-0411 release notes?

[nedbat]

Ugh, I guess the ideal would be that the Eucalyptus release notes are published from the eucalyptus branch, so that master could advance without worry.

But we don't have that. I guess the best thing now is to leave the coursetalk page with a warning at the top that it's for historical use only. Maybe it can be removed from the index of the book so it's only found if linked to?

[sarina]

@nedbat @marcotuts this is ready to review, I'll squash commits once review is done