docs: fix misleading require-approval timeout-minutes comment in create prompt (#1475)

The comment 'Optional: 24h default' implied that 1440 minutes was the
default value for timeout-minutes, when in fact the field defaults to
None (inheriting the pipeline/job timeout). Updated to clarify that
1440 is an example value and that omitting the field uses the pipeline
default — consistent with docs/safe-outputs.md which already says
'omit → pipeline default'.

Co-authored-by: github-actions[bot] <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: github-actions[bot]

prompts/create-ado-agentic-workflow.md

@@ -427,7 +427,7 @@ safe-outputs:
     require-approval:
       approvers: ["my-ado-group", "jane@example.com"]  # Optional: specific approvers
       notify-users: ["jane@example.com"]                # Optional: users to notify
-      timeout-minutes: 1440                             # Optional: 24h default
+      timeout-minutes: 1440                             # Optional: e.g. 1440 for 24h; omit → pipeline/job timeout applies
       on-timeout: reject                                # "reject" (default) or "resume"
       instructions: "Review the proposed PR carefully." # Optional: reviewer instructions
 ```