Support `init.defaultBranch` Git configuration option.

functions/fish_prompt.fish

@@ -47,7 +47,7 @@ function __bobthefish_git_branch -S -d 'Get the current git branch (or commitish
     set -l branch (command git symbolic-ref HEAD 2>/dev/null | string replace -r '^refs/heads/' '')
     and begin
         [ -n "$theme_git_default_branches" ]
-        or set -l theme_git_default_branches master main
+        or set -l theme_git_default_branches master main (git config init.defaultBranch)
 
         [ "$theme_display_git_master_branch" != 'yes' -a "$theme_display_git_default_branch" != 'yes' ]
         and contains $branch $theme_git_default_branches