text: Title: [Bug] pip install -e .[all,dev,notebooks] giving an error
  Body: ### Describe the bug
  
  In the instructions under "Install TTS", there is command to install extras that is causing me an error when I run it:
  
  `pip install -e .[all,dev,notebooks]  # Select the relevant extras`
  
  
  
  
  
  ### To Reproduce
  
  I tried each one of those options: [all, dev, notebooks]
  ```
  `pip install -e . all`
  `pip install -e . dev`
  `pip install -e . notebooks`
  ```
  They all came back with an error something like this:
  ```
  steve@gpu2:~/workspace/TTS$ pip3.10 install -e . dev
  Defaulting to user installation because normal site-packages is not writeable
  Obtaining file:///home/steve/workspace/TTS
    Installing build dependencies ... done
    Checking if build backend supports build_editable ... done
    Getting requirements to build editable ... done
    Preparing editable metadata (pyproject.toml) ... done
  ERROR: Could not find a version that satisfies the requirement dev (from versions: none)
  ERROR: No matching distribution found for dev
  ```
  Am I entering this command in wrong?  Notice that there is no space between . and [ in the original command listed in the read.me.  I am assuming there is a space in between.  Not putting there results in the following error:
  ```
  steve@gpu2:~/workspace/TTS$ pip3.10 install -e .all
  Defaulting to user installation because normal site-packages is not writeable
  ERROR: .all is not a valid editable requirement. It should either be a path to a local project or a VCS URL (beginning with bzr+http, bzr+https, bzr+ssh, bzr+sftp, bzr+ftp, bzr+lp, bzr+file, git+http, git+https, git+ssh, git+git, git+file, hg+file, hg+http, hg+https, hg+ssh, hg+static-http, svn+ssh, svn+http, svn+https, svn+svn, svn+file).
  ```
  
  It's been some time since I have worked in linux, so forgive me if this is obvious.  Thanks!
  
  ### Expected behavior
  
  I am not expecting an error message.
  
  ### Logs
  
  _No response_
  
  ### Environment
  
  ```shell
  I don't even have a bin directory yet.
  ```
  
  
  ### Additional context
  
  _No response_