CI Changes for main branch migration (#54)

Update links to main branch for doc links.

Signed-off-by: Danno Ferrin <[email protected]>

MAINTAINERS.md

@@ -1,3 +1,3 @@
 # Maintainers
 
-This repository follows the same maintainership as the main [Hyperledger Besu Maintainers](https://github.com/hyperledger/besu/blob/master/MAINTAINERS.md)
+This repository follows the same maintainership as the main [Hyperledger Besu Maintainers](https://github.com/hyperledger/besu/blob/main/MAINTAINERS.md)

README.md

@@ -1,7 +1,7 @@
 # homebrew-besu
  [![RocketChat chat](https://open.rocket.chat/images/join-chat.svg)](https://chat.hyperledger.org/channel/besu)
  [![Documentation Status](https://readthedocs.org/projects/hyperledger-besu/badge/?version=latest)](https://besu.hyperledger.org/en/latest/?badge=latest)
- [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/hyperledger/homebrew-besu/blob/master/LICENSE)
+ [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/hyperledger/homebrew-besu/blob/main/LICENSE)
 Homebrew Tap for besu.
 
 ## Getting started