Incorrect branch for the deposit-cli

When I choose generate keys / build from source / install deposit-cli, there is a following text:

```If you’re a git user, you can run git clone -b master --single-branch https://github.com/eth-educators/ethstaker-deposit-cli.git to download the master branch.```

But this branch is not updated more than 1 year and doesn't contain latest features like `--compounding` option. The right branch seems to be "main" not "master".