Update github-trigger-event-options.adoc

[BeFunes]

Description

A brief description of the changes.

Reasons

A link to a GitHub and/or JIRA issue (if applicable).
Otherwise, a brief sentence about why you made these changes.

Content Checklist

Please follow our style when contributing to CircleCI docs. Our style guide is here: https://circleci.com/docs/style/style-guide-overview.

Please take a moment to check through the following items when submitting your PR (this is just a guide so will not be relevant for all PRs) 😸:

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