chore: remove gtk settings backup

dotfiles/config/gtk-3.0/settings.ini.hm-backup

@@ -1,24 +0,0 @@
-[Settings]
-gtk-application-prefer-dark-theme=true
-gtk-button-images=1
-gtk-cursor-theme-name=breeze_cursors
-gtk-cursor-theme-size=24
-gtk-decoration-layout=icon:minimize,maximize,close
-gtk-enable-animations=true
-gtk-enable-event-sounds=1
-gtk-enable-input-feedback-sounds=1
-gtk-fallback-icon-theme=gnome
-gtk-font-name=Noto Sans 11
-gtk-icon-theme-name=Numix-Circle
-gtk-key-theme-name=Emacs
-gtk-menu-images=1
-gtk-modules=colorreload-gtk-module
-gtk-primary-button-warps-slider=false
-gtk-theme-name=Arc
-gtk-toolbar-icon-size=GTK_ICON_SIZE_LARGE_TOOLBAR
-gtk-toolbar-style=GTK_TOOLBAR_BOTH_HORIZ
-gtk-xft-antialias=1
-gtk-xft-dpi=107520
-gtk-xft-hinting=1
-gtk-xft-hintstyle=hintslight
-gtk-xft-rgba=rgb