refactor: migrate php to inline product options syntax (#13411)

Author: a-hariti

docs/platforms/php/index.mdx

@@ -45,13 +45,17 @@ The Excimer PHP extension supports PHP 7.2 and up. Excimer requires Linux or mac
 To capture all errors, even the one during the startup of your application, you should initialize the Sentry PHP SDK as soon as possible.
 
 
-```php {"onboardingOptions": {"performance": "3-4", "profiling": "5-6"}}
+```php
 \Sentry\init([
   'dsn' => '___PUBLIC_DSN___',
+  // ___PRODUCT_OPTION_START___ performance
   // Specify a fixed sample rate
   'traces_sample_rate' => 1.0,
+  // ___PRODUCT_OPTION_END___ performance
+  // ___PRODUCT_OPTION_START___ profiling
   // Set a sampling rate for profiling - this is relative to traces_sample_rate
   'profiles_sample_rate' => 1.0,
+  // ___PRODUCT_OPTION_END___ profiling
 ]);
 ```