fix: change the default status line background to mantle (#377)

Author: kjnsn

catppuccin_tmux.conf

@@ -1,7 +1,7 @@
 source -F "#{d:current_file}/themes/catppuccin_#{@catppuccin_flavor}_tmux.conf"
 
 %if "#{==:#{@catppuccin_status_background},default}"
-  set -gF @_ctp_status_bg "#{@thm_surface_1}"
+  set -gF @_ctp_status_bg "#{@thm_mantle}"
   set -gF status-style "bg=#{@_ctp_status_bg},fg=#{@thm_fg}"
 
   %hidden CTP_MESSAGE_BACKGROUND="#{@thm_surface_0}"

tests/application_module_expected.txt

@@ -1 +1 @@
-@catppuccin_status_application #[fg=#f5c2e7,nobold,nounderscore,noitalics]#[fg=#11111b,bg=#f5c2e7] #[fg=#f5c2e7,bg=#45475a]#[fg=#cdd6f4] #{E:@catppuccin_application_text}#[fg=#45475a]█
+@catppuccin_status_application #[fg=#f5c2e7,nobold,nounderscore,noitalics]#[fg=#11111b,bg=#f5c2e7] #[fg=#f5c2e7,bg=#181825]#[fg=#cdd6f4] #{E:@catppuccin_application_text}#[fg=#181825]█

tests/battery_module_expected.txt

@@ -1 +1 @@
-@catppuccin_status_battery #[fg=#f9e2af,nobold,nounderscore,noitalics]#[fg=#11111b,bg=#f9e2af]#{l:#{battery_icon}} #[fg=#f9e2af,bg=#45475a]#[fg=#cdd6f4] #{E:@catppuccin_battery_text}#[fg=#45475a]█
+@catppuccin_status_battery #[fg=#f9e2af,nobold,nounderscore,noitalics]#[fg=#11111b,bg=#f9e2af]#{l:#{battery_icon}} #[fg=#f9e2af,bg=#181825]#[fg=#cdd6f4] #{E:@catppuccin_battery_text}#[fg=#181825]█

tests/cpu_module_expected.txt

@@ -1 +1 @@
-E:@catppuccin_status_cpu #[fg=#{cpu_bg_color},nobold,nounderscore,noitalics]#[fg=#11111b,bg=#{cpu_bg_color}] #[fg=#{cpu_bg_color},bg=#45475a]#[fg=#cdd6f4] #{cpu_percentage}#[fg=#45475a]█
+E:@catppuccin_status_cpu #[fg=#{cpu_bg_color},nobold,nounderscore,noitalics]#[fg=#11111b,bg=#{cpu_bg_color}] #[fg=#{cpu_bg_color},bg=#181825]#[fg=#cdd6f4] #{cpu_percentage}#[fg=#181825]█