Typo fix in webpack.config.dev.js comments (#777)

* Typo fix in webpack.config.dev.js comments

* Typo fix in webpack.config.prod.js comments

packages/react-scripts/config/webpack.config.dev.js

@@ -27,7 +27,7 @@ var publicPath = '/';
 // as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
 // Omit trailing shlash as %PUBLIC_PATH%/xyz looks better than %PUBLIC_PATH%xyz.
 var publicUrl = '';
-// Get enrivonment variables to inject into our app.
+// Get environment variables to inject into our app.
 var env = getClientEnvironment(publicUrl);
 
 // This is the development configuration.

packages/react-scripts/config/webpack.config.prod.js

@@ -44,7 +44,7 @@ var publicPath = ensureSlash(homepagePathname, true);
 // as %PUBLIC_URL% in `index.html` and `process.env.PUBLIC_URL` in JavaScript.
 // Omit trailing shlash as %PUBLIC_PATH%/xyz looks better than %PUBLIC_PATH%xyz.
 var publicUrl = ensureSlash(homepagePathname, false);
-// Get enrivonment variables to inject into our app.
+// Get environment variables to inject into our app.
 var env = getClientEnvironment(publicUrl);
 
 // Assert this just to be safe.