Unset SYSTEMD_COLORS for systemd completion

Fixes an issue where systemctl and other systemd commands completions are prefixed by ANSI color escape codes

share/functions/__fish_systemctl.fish

@@ -1,4 +1,7 @@
 function __fish_systemctl --description 'Call systemctl with some options from the current commandline'
+    # We don't want to complete with ANSI color codes
+    set -lu SYSTEMD_COLORS
+
     # These options are all global - before or after subcommand/arguments.
     # There's a bunch of long-only options in here, so we need to be creative with the mandatory short version.
     set -l opts t/type= s-state= p/property= a/all

share/functions/__fish_systemctl_services.fish

@@ -1,4 +1,7 @@
 function __fish_systemctl_services
+    # We don't want to complete with ANSI color codes
+    set -lu SYSTEMD_COLORS
+
     if type -q systemctl
         if __fish_contains_opt user
             systemctl --user list-unit-files --full --no-legend --no-pager --plain --type=service 2>/dev/null $argv | string split -f 1 ' '

share/functions/__fish_systemd_machine_images.fish

@@ -1,6 +1,9 @@
 # Like for running machines, I'm assuming machinectl doesn't allow spaces in image names
 # This does not include the special image ".host" since it isn't valid for most operations
 function __fish_systemd_machine_images
+    # We don't want to complete with ANSI color codes
+    set -lu SYSTEMD_COLORS
+
     machinectl --no-legend --no-pager list-images | while read -l a b
         echo $a
     end

share/functions/__fish_systemd_machines.fish

@@ -1,5 +1,8 @@
 # It seems machinectl will eliminate spaces from machine names so we don't need to handle that
 function __fish_systemd_machines
+    # We don't want to complete with ANSI color codes
+    set -lu SYSTEMD_COLORS
+
     machinectl --no-legend --no-pager list --all | while read -l a b
         echo $a
     end