Update contribution guidelines to state usage of Prettier

CONTRIBUTING.md

@@ -132,18 +132,13 @@ This will run all tests and watch source and test files for changes. When a chan
 
 #### Coding Style
 
-To maximize the readability and correctness of our code, we require that new submissions follow the
-[JavaScript Standard Style](https://standardjs.com/).
-
-Before committing, please run:
+For consistency and readability, we require that new submissions follow the [Prettier Style](https://prettier.io/).
+Before committing, please format your code automatically using Prettier by running the following command:
 
 ```bash
 npm run style
 ```
 
-In order to apply the coding style (where it can be done automatically). If an error is shown, please figure out what's
-wrong, fix it and run standard again.
-
 A few (but not all) of the things to keep in mind:
 
 - Use camelCase with the leading character as lowercase for identifier names (variables and functions).