Add gitgraph.nvim

[dormeiri]

🎉 First off, thanks for taking the time to contribute! 🎉

Here are some guidelines:

• Format code using stylua.
• New plugin integration should be added in alphabetical order:
  • to the README (vimdoc is auto-generated).
  • to types.lua
• Create a topic branch on your fork for your specific PR.
• Use conventionalcommits.org's
  rules for explicit and meaningful commit messages.
• If it's your first time contributing to a project, then read
  About pull requests
  on Github's docs.

Here are some tips:

• Use vim.g.catppuccin_debug = true to get live config re-loading

[vollowx]

Missing a <

[vollowx]

Remove this line as integrations are disabled by default.