Docs: Update "How to run things locally" (#24097)

* Recommend a local server, don't present it as second option

Current wording offers two options and suggests we'll explain both, but then only explains the second. As discussed in #15334  we should not encourage users to change their browser's security settings.

* Clean up

Author: donmccurdy

docs/manual/en/introduction/How-to-run-things-locally.html

@@ -21,21 +21,19 @@ <h2>Content loaded from external files</h2>
 			 	security restrictions, loading from a file system will fail with a security exception.
 		 	</p>
 
-			<p>There are two ways to solve this:</p>
-
-			<ol>
-				<li>
-					Change security for local files in a browser. This allows you to access your page as: <code>file:///yourFile.html</code>
-				</li>
-				<li>
-					Run files from a local web server. This allows you to access your page as: <code>http://localhost/yourFile.html</code>
-				</li>
-			</ol>
+			<p>
+				To solve this, run files from a local web server. This allows you to access your page as:
+			</p>
+			
+			<p>
+				<code>http://localhost/yourFile.html</code>
+			</p>
 
 			<p>
-				If you use option 1, be aware that you may open yourself to some vulnerabilities if using
-				the same browser for a regular web surfing. You may want to create a separate browser
-				profile / shortcut used just for local development to be safe. Let's go over each option in turn.
+				While it is also possible to change browser security settings instead of running a local server,
+				we do not recommend that approach. Doing so may open your device up to vulnerabilities, if the
+				same browser is used for regular web surfing. Use of a local server is standard practice in 
+				web development, and we explain how to install and use a local server below.
 			</p>
 		</div>