Remove reference to website in iOS session replay doc (#13873)

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Replaces "website" with "app" in iOS session replay doc.

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Author: jvanderwee

docs/platforms/apple/guides/ios/session-replay/index.mdx

@@ -52,7 +52,7 @@ Once testing is complete, **we recommend lowering this value in production**. We
 
 ## Sampling
 
-Sampling allows you to control how much of your website's traffic will result in a Session Replay. There are two sample rates you can adjust to get the replays relevant to you:
+Sampling allows you to control how much of your app's traffic will result in a Session Replay. There are two sample rates you can adjust to get the replays relevant to you:
 
 1. `sessionSampleRate` - The sample rate for
    replays that begin recording immediately and last the entirety of the user's session.