Describe the bug
A clear and concise description of what the bug is.
Tmuxinator will run the command twice when shell is using on-my-zsh that takes terminal 3-5 seconds to load

To Reproduce
Steps to reproduce the behavior.
When .zshrc file is huge (takes around 5 seconds to intialize), each window/pane startup command will be run twice

Expected behavior
A clear and concise description of what you expected to happen.

Environment

• tmuxinator Version: tmuxinator 2.0.2[output of tmuxinator -v, e.g. "tmuxinator 0.13.0"]
• tmux Version: tmux 3.1c [output of tmux -V, e.g. "tmux 2.3"]
• Ruby Version: ruby 2.6.3p62 (2019-04-16 revision 67580) [universal.x86_64-darwin20] [output of ruby -v, e.g. "ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]"]
• OS: macos BigSur [specific command varies, e.g. "Debian GNU/Linux 9.5 (stretch)"]

Additional information
Add any other context or (potentially) useful information about the problem here. Feel free to include screenshots, videos, scripts, Dockerfiles, etc. which may help others diagnose/reproduce the issue.