remove lgtm shut down (#5014)

Signed-off-by: Gabriel Fukushima <gabrielfukushima@gmail.com>

README.md

@@ -1,7 +1,5 @@
 # Besu Ethereum Client
  [![CircleCI](https://circleci.com/gh/hyperledger/besu/tree/main.svg?style=svg)](https://circleci.com/gh/hyperledger/besu/tree/main)
- [![Total alerts](https://img.shields.io/lgtm/alerts/g/hyperledger/besu.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/hyperledger/besu/alerts/)
- [![Language grade: Java](https://img.shields.io/lgtm/grade/java/g/hyperledger/besu.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/hyperledger/besu/context:java)
  [![Documentation Status](https://readthedocs.org/projects/hyperledger-besu/badge/?version=latest)](https://besu.hyperledger.org/en/latest/?badge=latest)
  [![CII Best Practices](https://bestpractices.coreinfrastructure.org/projects/3174/badge)](https://bestpractices.coreinfrastructure.org/projects/3174)
  [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/hyperledger/besu/blob/main/LICENSE)