feat(nvim): link winbar to statusline

Preserves Neovim's default prior to release v0.10, after which hl-WinBar
got hardcoded to the color used in Neovim's (new) default colorscheme
(neovim/neovim#26921).

Closes #203

colors/gruvbox-material.vim

@@ -10,7 +10,7 @@
 let s:configuration = gruvbox_material#get_configuration()
 let s:palette = gruvbox_material#get_palette(s:configuration.background, s:configuration.foreground, s:configuration.colors_override)
 let s:path = expand('<sfile>:p') " the path of this script
-let s:last_modified = 'Fri May 17 09:33:15 UTC 2024'
+let s:last_modified = 'Sun May 19 06:38:06 PM UTC 2024'
 let g:gruvbox_material_loaded_file_types = []
 
 if !(exists('g:colors_name') && g:colors_name ==# 'gruvbox-material' && s:configuration.better_performance)
@@ -255,7 +255,8 @@ call gruvbox_material#highlight('debugBreakpoint', s:palette.bg0, s:palette.red)
 call gruvbox_material#highlight('ToolbarButton', s:palette.bg0, s:palette.grey2)
 if has('nvim')
   call gruvbox_material#highlight('Substitute', s:palette.bg0, s:palette.yellow)
-  highlight! link WinBarNC Grey
+  highlight! link WinBar StatusLine
+  highlight! link WinBarNC StatusLineNC
   highlight! link DiagnosticFloatingError ErrorFloat
   highlight! link DiagnosticFloatingWarn WarningFloat
   highlight! link DiagnosticFloatingInfo InfoFloat