fix themes

patches/add-black-theme.patch

@@ -6,4 +6,4 @@ index 000000000..5598dbea0
 @@ -0,0 +1,3 @@
 +$ui-base-color: #000000;
 +
-+@import 'application';
++@use 'application';

patches/add-merveilles-theme.patch

@@ -7,4 +7,4 @@ index 000000000..5147ae626
 +$ui-base-color: #222222;
 +$ui-highlight-color: #333333;
 +
-+@import "application";
++@use 'application';

patches/add-tango-theme.patch

@@ -23,4 +23,4 @@ index 000000000..9699d17b5
 +$ui-button-tertiary-focus-background-color: #3d6085;
 +$ui-button-icon-hover-background-color: rgba(74, 115, 160, 40%);
 +
-+@import 'application';
++@use 'application';