Add space before two dots

Co-authored-by: Antonio Tripodi <[email protected]>

Author: cyrilchapon

content/first-steps.md

@@ -153,7 +153,7 @@ A Nest cli scaffolded project uses
 
 ##### Code style
 
-With this stack setup, by default we ensure the resulting code follows :
+With this stack setup, by default we ensure the resulting code follows:
 - Typescript eslint [recommended rules](https://github.com/typescript-eslint/typescript-eslint/blob/main/packages/eslint-plugin/src/configs/recommended.ts)
 - Improved with some [rules in `.eslintrc.js` file](https://github.com/nestjs/typescript-starter/blob/master/.eslintrc.js)
 - Prettier [default options](https://prettier.io/docs/en/options.html)