Simplify some Option / Result / ? operator patterns (#8653)

* Simplify some Option / Result / ? operator patterns

When those match a combinator exactly.

Tool-aided by [comby-rust](https://github.com/huitseeker/comby-rust).

* adjust after review

* adjust post-review

substrate/client/telemetry/src/lib.rs

@@ -389,10 +389,7 @@ impl Telemetry {
 	/// The `connection_message` argument is a JSON object that is sent every time the connection
 	/// (re-)establishes.
 	pub fn start_telemetry(&mut self, connection_message: ConnectionMessage) -> Result<()> {
-		let endpoints = match self.endpoints.take() {
-			Some(x) => x,
-			None => return Err(Error::TelemetryAlreadyInitialized),
-		};
+		let endpoints = self.endpoints.take().ok_or_else(|| Error::TelemetryAlreadyInitialized)?;
 
 		self.register_sender
 			.unbounded_send(Register::Telemetry {