neat (docs) remove double commas (#15582)

Author: sergical

platform-includes/getting-started-tunneling/javascript.mdx

@@ -4,7 +4,7 @@ To enable tunneling, update `Sentry.init` with the following option:
 
 ```javascript {3}
 Sentry.init({
-  dsn: "___PUBLIC_DSN___",,
+  dsn: "___PUBLIC_DSN___",
   tunnel: "/tunnel",
 });
 ```

platform-includes/getting-started-tunneling/javascript.remix.mdx

@@ -4,7 +4,7 @@ To enable tunneling, update `Sentry.init` in your `entry.client.tsx` file with t
 
 ```javascript {filename:entry.client.tsx}{3}
 Sentry.init({
-  dsn: "___PUBLIC_DSN___",,
+  dsn: "___PUBLIC_DSN___",
   tunnel: "/tunnel",
 });
 ```

platform-includes/getting-started-tunneling/javascript.sveltekit.mdx

@@ -4,7 +4,7 @@ To enable tunneling, update `Sentry.init` in your `hooks.client.(js|ts)` file wi
 
 ```javascript {filename:hooks.client.(js|ts)} {3}
 Sentry.init({
-  dsn: "___PUBLIC_DSN___",,
+  dsn: "___PUBLIC_DSN___",
   tunnel: "/tunnel",
 });
 ```