Remove Reference to Copilot Pro Trial (#60780)

Author: krshearman

content/copilot/get-started/what-is-github-copilot.md

@@ -66,7 +66,6 @@ You can start using {% data variables.product.prodname_copilot_short %} in sever
 
 * **Try {% data variables.product.prodname_copilot_short %} for free.** Use {% data variables.copilot.copilot_free_short %} to explore core features with no paid plan required.
 * **Subscribe to a paid plan.** Upgrade to {% data variables.copilot.copilot_pro_short %} or {% data variables.copilot.copilot_pro_plus_short %} for full access to premium features and more generous usage limits. 
-  * Try <a href="https://github.com/github-copilot/signup?ref_product=copilot&ref_type=trial&ref_style=text&ref_plan=pro" target="_blank"><span>{% data variables.copilot.copilot_pro_short %} for free</span></a> with a one-time 30-day trial.
 * **Get free access if you're eligible.** Students, teachers, and open source maintainers may qualify for access to premium features at no cost. See [AUTOTITLE](/copilot/how-tos/copilot-on-github/set-up-copilot/enable-copilot/set-up-for-students) and [AUTOTITLE](/copilot/how-tos/copilot-on-github/set-up-copilot/enable-copilot/set-up-for-teachers-and-os-maintainers).
 * **Request access from your organization.** If your organization or enterprise has a {% data variables.product.prodname_copilot %} plan, you can request access by going to [https://github.com/settings/copilot](https://github.com/settings/copilot) and request access under "Get {% data variables.product.prodname_copilot_short %} from an organization."