remove refs to zowe-chat in current doc

[MarkAckert]

Describe your pull request here:

Removes references to zowe-chat in the zowe docs per the TSC discussion on Oct 9 where we agreed to remove Zowe Chat's incubator status.

If we ever decided to bring Zowe Chat back, start by reverting the changes from this PR.

Older, versioned areas of the zowe docs will retain links to zowe chat, and should continue to work.

List the file(s) included in this PR:

• everything.md
• Removed 60 files related to zowe-chat.

After creating the PR, follow the instructions in the comments.

[github-actions]

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[github-actions]

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[github-actions]

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