Use main branch to point to config

Author: schlessera

README.md

@@ -36,7 +36,7 @@ SUBCOMMANDS
 
 ### How to translate
 
-1. Add your language to `[_config.yml](https://github.com/wp-cli/wp-cli.github.com/blob/master/_config.yml)`.
+1. Add your language to `[_config.yml](https://github.com/wp-cli/wp-cli.github.com/blob/main/_config.yml)`.
 2. Create a folder under the name of your appropriate language code (IETF language tag). e.g. ja or pt_BR
 3. Copy the *English* `index.md` into your language's directory.
 4. Translate `index.md`.