ref(profiling): define client_sdk as required in profiling sample format v2 (#14135)

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Author: viglia

develop-docs/sdk/telemetry/profiles/sample-format-v2.mdx

@@ -78,9 +78,9 @@ The *Sample Format V2* is designed for use in continuous profiling. Therefore, a
 
 `client_sdk`
 
-: *Object, optional.* Contains information about the client *SDK*.
+: *Object, required.* Contains information about the client *SDK*.
 
-It can have the following attributes:
+It has the following attributes:
 - `name`
 - `version`