Remove documented default model from Copilot CLI model usage docs (#61357)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: crwaters16 <78226508+crwaters16@users.noreply.github.com>

Author: Copilot

content/copilot/concepts/agents/copilot-cli/about-copilot-cli.md

@@ -303,8 +303,6 @@ For more information about these policies, see [AUTOTITLE](/copilot/concepts/mcp
 
 ## Model usage
 
-The default model used by {% data variables.copilot.copilot_cli %} is {% data variables.copilot.copilot_claude_sonnet_45 %}. {% data variables.product.github %} reserves the right to change this model.
-
 You can change the model used by {% data variables.copilot.copilot_cli %} by using the `/model` slash command or the `--model` command-line option. Enter this command, then select a model from the list.
 
 Each time you submit a prompt to {% data variables.product.prodname_copilot_short %} in {% data variables.copilot.copilot_cli_short %}'s interactive interface, and each time you use {% data variables.copilot.copilot_cli_short %} programmatically, your monthly quota of {% data variables.product.prodname_copilot_short %} premium requests is reduced by one, multiplied by the multiplier shown in parentheses in the model list. For example, `Claude Sonnet 4.5 (1x)` indicates that with this model each time you submit a prompt your quota of premium requests is reduced by one. For information about premium requests, see [AUTOTITLE](/copilot/concepts/billing/copilot-requests).