[Expo] Add Expo Updates Guide to Docs

[krystofwoldrich]

Document current Expo Updates integration and what information is automatically collected.

Add guide for how Releases can be create for each update.

import * as Updates from "expo-updates";
import * as Application from "expo-application";
import * as Sentry from "@sentry/react-native";

const name = Application.applicationName ?? "unknown-name";
const version = Application.nativeApplicationVersion ?? "unknown-version";
const build = Application.nativeBuildVersion ?? "unknown-build";
const updateId = Updates.isEmbeddedLaunch ? null : Updates.updateId;
const channel = Updates.channel || "development";
const release = updateId
  ? `${name}@${version}+${build}#${channel}:${updateId}`
  : `${name}@${version}+${build}#${channel}`;

Sentry.init({
  // ...rest
  release,
});