docs: update getting started (#2518)

* docs: update getting started 

Starting with husky 5.2.0, `husky add ...` will append command or create a new file

* docs: update guides-local-setup

Author: typicode

README.md

@@ -112,16 +112,6 @@ npx husky add .husky/commit-msg "npx --no-install commitlint --edit $1"
 yarn husky add .husky/commit-msg "yarn commitlint --edit $1"
 ```
 
-If the file `.husky/commit-msg` already exists, you can edit the file and put this:
-
-```sh
-# .husky/commit-msg
-# ...
-npx --no-install commitlint --edit $1
-# or
-yarn commitlint --edit $1
-```
-
 **Detailed Setup instructions**
 
 - [Local setup](https://conventional-changelog.github.io/commitlint/#/guides-local-setup) - Lint messages on commit with husky

docs/guides-local-setup.md

@@ -38,16 +38,6 @@ npx husky add .husky/commit-msg 'npx --no-install commitlint --edit $1'
 yarn husky add .husky/commit-msg 'yarn commitlint --edit $1'
 ```
 
-If the file `.husky/commit-msg` already exists, you can edit the file and put this:
-
-```sh
-# .husky/commit-msg
-# ...
-npx --no-install commitlint --edit $1
-# or
-yarn commitlint --edit $1
-```
-
 ## Test
 
 ### Test simple usage