Docs: Add `Epic` support to the list of target types

What does this MR do and why?

Add Epic support to the list of target types in Webhook documentation

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

NA

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

#491777 (closed) #430080 (closed)

added devopsplan docs-only groupproduct planning labels

assigned to @kushalpandya

changed the description

added sectiondev label

Proper labels assigned to this merge request. Please ignore me.

👋 @kushalpandya - please see the following guidance and update this merge request.

	1 Error
❌	Please add typebug typefeature, or typemaintenance label to this merge request.

added documentation label

	1 Message
📖	This merge request adds or changes documentation files. A review from the Technical Writing team before you merge is recommended. Reviews can happen after you merge.

Documentation review

The following files require a review from a technical writer:

• doc/api/events.md (Link to current live version)

The review does not need to block merging this merge request. See the:

• Metadata for the *.md files that you've changed. The first few lines of each *.md file identify the stage and group most closely associated with your docs change.
• The Technical Writer assigned for that stage and group.
• Documentation workflows for information on when to assign a merge request for review.

If needed, you can retry the 🔁 danger-review job that generated this comment.

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mentioned in issue #430080 (closed)

requested review from @phillipwells

added Technical Writing devopsgovern docsimprovement groupcompliance maintenancerefactor typemaintenance labels and removed devopsplan groupproduct planning labels

@kushalpandya I left a comment and a question for you here 🏓 Thanks!

changed milestone to %17.5

removed review request for @phillipwells

added 1 commit

• 50c51fea - Add `Epic` support to the list of target types

Compare with previous version

requested review from @phillipwells

approved this merge request

removed review request for @phillipwells

requested review from @phillipwells