feat(ui): make info-prompt icon looks like the letter "i" (#1835)

Author: cotes2020

_sass/addon/commons.scss

@@ -107,8 +107,8 @@ blockquote {
     }
   }
 
-  @include prompt('tip', '\f0eb', 'regular');
-  @include prompt('info', '\f06a');
+  @include prompt('tip', '\f0eb', $fa-style: 'regular');
+  @include prompt('info', '\f06a', $rotate: 180);
   @include prompt('warning', '\f06a');
   @include prompt('danger', '\f071');
 }

_sass/addon/module.scss

@@ -187,14 +187,18 @@
   transform: translateX(-50%);
 }
 
-@mixin prompt($type, $fa-content, $fa-style: 'solid') {
+@mixin prompt($type, $fa-content, $fa-style: 'solid', $rotate: 0) {
   &.prompt-#{$type} {
     background-color: var(--prompt-#{$type}-bg);
 
     &::before {
       content: $fa-content;
       color: var(--prompt-#{$type}-icon-color);
       font: var(--fa-font-#{$fa-style});
+
+      @if $rotate != 0 {
+        transform: rotate(#{$rotate}deg);
+      }
     }
   }
 }