Update environment.md build doc to install lzma: (#4498)

On macOS, if you have not installed something that depends on `xz`, then your
system may lack `lzma`, resulting in a build error similar to:

```
Downloading libarchive-3.6.0.tar.xz completed [6250.61k]
libarchive/3.6.0: 
ERROR: libarchive/3.6.0: Error in source() method, line 120
        get(self, **self.conan_data["sources"][self.version], strip_root=True)
        ReadError: file could not be opened successfully:
- method gz: ReadError('not a gzip file')
- method bz2: ReadError('not a bzip2 file')
- method xz: CompressionError('lzma module is not available')
- method tar: ReadError('invalid header')
```

The solution is to ensure that `lzma` is installed by installing `xz`.

docs/build/environment.md

@@ -69,6 +69,7 @@ and use it to install Conan:
 ```
 /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
 brew update
+brew install xz
 brew install pyenv
 pyenv install 3.10-dev
 pyenv global 3.10-dev