Add Flox to installation options

[bryanhonof]

lazydocker is available and working in Flox today.

$ cd "$(mktemp -d)"
$ flox init
✨ Created environment 'tmp.exxnTQQsGK' (aarch64-darwin)

Next:
  $ flox search <package>    <- Search for a package
  $ flox install <package>   <- Install a package into an environment
  $ flox activate            <- Enter the environment
  $ flox edit                <- Add environment variables and shell hooks

$ flox install lazydocker
✅ 'lazydocker' installed to environment 'tmp.exxnTQQsGK'
$ flox activate -- lazydocker --version
Version: 0.23.3
Date:
BuildSource: unknown
Commit:
OS: darwin
Arch: arm64