css cleanup: fix few warnings

Author: maxcom

src/main/webapp/sass/_common.scss

@@ -25,7 +25,7 @@
 @use "topic_page";
 @use "tag_page";
 @use "reactions";
+@use "cal-heapmap";
 
-@import "cal-heapmap";
-@import "tracker";
 @import "spoilers";
+@import "tracker";