same text-color as background for nav-item:hover dropdown (#1939)

* fix(scss): same text-color as background for nav-item:hover dropdown

https://github.com/almasaeed2010/AdminLTE/issues/1893

* fix(scss): same text-color as background for nav-item:hover dropdown

https://github.com/almasaeed2010/AdminLTE/issues/1893

build/scss/_navs.scss

@@ -6,8 +6,10 @@
   .nav-link {
     color: $gray-600;
 
-    &:not(.active):hover {
-      color: theme-color("primary")
+    &:not(.active) {
+      &:not(.dropdown-toggle):hover {
+        color: theme-color("primary")
+      }
     }
   }
 }