Move carets into misc stylesheet

ui/src/style/theme/_dropdowns.scss

@@ -93,26 +93,7 @@ $dropdown-purple-header: $c-potassium;
   align-items: center;
 
   .caret {
-    position: absolute;
-    top: calc(50% + 1px);
     right: $form-md-padding;
-    transform: translateY(-50%);
-    width: 11px;
-    height: 16px;
-
-    &:after {
-      content: "\e902";
-      font-family: 'icomoon' !important;
-      -webkit-font-smoothing: antialiased;
-      -moz-osx-font-smoothing: grayscale;
-      color: inherit;
-      display: inline;
-      position: absolute;
-      top: 50%;
-      left: 50%;
-      transform: translate(-50%,-55%);
-      font-size: 11px;
-    }
   }
 
   > .icon {

ui/src/style/theme/_misc.scss

@@ -0,0 +1,27 @@
+/*
+   Miscellaneous
+   -----------------------------------------------------------------------------
+*/
+
+.caret {
+  position: absolute;
+  top: calc(50% + 1px);
+  right: $form-md-padding;
+  transform: translateY(-50%);
+  width: 11px;
+  height: 16px;
+
+  &:after {
+    content: "\e902";
+    font-family: 'icomoon' !important;
+    -webkit-font-smoothing: antialiased;
+    -moz-osx-font-smoothing: grayscale;
+    color: inherit;
+    display: inline;
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    transform: translate(-50%,-55%);
+    font-size: 11px;
+  }
+}

ui/src/style/theme/chronograf-theme.scss

@@ -14,3 +14,4 @@
 @import 'alerts';
 @import 'panels';
 @import 'radio-buttons';
+@import 'misc';