add symbols-only-nerd-font to fonts brewfile

Author: inffy

system_files/shared/usr/share/ublue-os/homebrew/aurora-fonts.Brewfile

@@ -8,3 +8,4 @@ cask "font-source-code-pro"
 cask "font-ubuntu-nerd-font"
 cask "font-fira-code-nerd-font"
 cask "font-monaspice-nerd-font"
+cask "font-symbols-only-nerd-font"