docs: no router redeploy required when updating percent label (#3192)

Clarify that no router redeploy is required to update percent label for
progressive override

Author: shorgi

docs/source/schema-design/federated-schemas/entities/migrate-fields.mdx

@@ -286,10 +286,10 @@ A few strategies to mitigate this concern:
 
 ### Customizing progressive `@override` behavior with a feature flag service
 
-Out of the box, the router supports the `percent(x)` syntax for resolving labels based on a given percentage. Unfortunately, updating this number requires a subgraph publish and router redeploy.
+Out of the box, the router supports the `percent(x)` syntax for resolving labels based on a given percentage. Updating this number requires publishing the subgraph.
 To avoid this, you can use a feature flag service to dynamically update the label value.
 
-The router provides an interface for coprocessors and rhai scripts to resolve arbitrary labels.
+The router provides an interface for coprocessors and Rhai scripts to resolve arbitrary labels.
 This lets you dial up or disable a label's rollout status without requiring a subgraph publish.
 A coprocessor or Rhai script that implements this should take the following steps: