Provide option to configure distro icon

[fourpastmidnight]

Requirements

Required Info

• [x] I have searched the issues for my issue and found nothing related and/or helpful
• [x] I have read or at least glanced at the FAQ
• [x] I have read or at least glanced at the Wiki
• [x] VimDevIcons is the last loaded vim plugin?
• [x] What version of vim are you using? 9.0
  • hint: vim --version
• [x] What font are you using? Caskaydia Cove NF
• [x] Are you using vim from the terminal or a GUI vim? Terminal
• [x] Are you using Mac, Linux or Windows? Manjaro Linux

Optional Info

• [ ] Provide screenshots where appropriate

I am requesting that this plugin provides a configuration variable such as g:WebDevIconsDistroIcon = "\uF312" to allow one to specify their Linux distribution. For example, I'm using Manjaro, and the Nerd Fonts have a Manjaro icon. Notably missing are other well-known distros, such as Fedora and Red Hat, Suse Linux, etc.