chore: adding 'no-experimental-fetch' node option by default (#25628)

CONTRIBUTING.md

@@ -643,18 +643,6 @@ There are three types of assets you can build:
 2. `npm run dev-server`: local development assets, with sourcemaps and hot refresh support
 3. `npm run build-instrumented`: instrumented application code for collecting code coverage from Cypress tests
 
-If this type of error comes while building assets(i.e using above commands):
-
-```bash
-Error: You must provide the URL of lib/mappings.wasm by calling SourceMapConsumer.initialize
-```
-
-Then put this:
-
-```bash
-export NODE_OPTIONS=--no-experimental-fetch
-```
-
 If while using the above commands you encounter an error related to the limit of file watchers:
 
 ```bash
@@ -663,7 +651,6 @@ Error: ENOSPC: System limit for number of file watchers reached
 The error is thrown because the number of files monitored by the system has reached the limit.
 You can address this this error by increasing the number of inotify watchers.
 
-
 The current value of max watches can be checked with:
 ```bash
 cat /proc/sys/fs/inotify/max_user_watches
@@ -680,6 +667,7 @@ To confirm that the change succeeded, run the following command to load the upda
 ```bash
 sudo sysctl -p
 ```
+
 #### Webpack dev server
 
 The dev server by default starts at `http://localhost:9000` and proxies the backend requests to `http://localhost:8088`.