docs: Update about-package-readme-files.mdx (#1296)

Use file and code format for README references

Author: kenshanta

content/packages-and-modules/contributing-packages-to-the-registry/about-package-readme-files.mdx

@@ -2,11 +2,11 @@
 title: About package README files
 ---
 
-To help others find your packages on npm and have a good experience using your code in their projects, we recommend including a README file in your package directory. Your README file may include directions for installing, configuring, and using the code in your package, as well as any other information a user may find helpful. The README file will be shown on the package page.
+We highly recommend including a `README.md` file in your package directory as it helps developers find your package on npm and have a good experience using your code in their projects. In most cases `README.md` files include directions for _installing_, _configuring_, and _using_ the code in your package; as well as any other information a user may find helpful. Just like in any GitHub repository, the `README.md` file will be rendered on the package's page.
 
-An npm package README file must be in the root-level directory of the package.
+An npm package `README.md` file **must** be in the root-level directory of the package.
 
-## Creating and adding a README.md file to a package
+## Creating and adding a `README.md` file to a package
 
 1. In a text editor, in your package root directory, create a file called `README.md`.
 2. In the `README.md` file, add useful information about your package.
@@ -18,9 +18,9 @@ An npm package README file must be in the root-level directory of the package.
 
 </Note>
 
-## Updating an existing package README file
+## Updating an existing package `README.md` file
 
-The README file will only be updated on the package page when you publish a new version of your package. To update your README file:
+The `README.md` file will only be updated on the package page when you publish a new version of your package. To update your `README.md` file:
 
 1. In a text editor, update the contents of the `README.md` file.