Toolkit: Improve styles on smaller screens

- Allow profile icons to shrink
- Make select go full-width

toolkit/scss/toolkit.scss

@@ -165,7 +165,6 @@ img {
         border-radius: 64px;
         border-width: 3px;
         border-style: solid;
-        height: 100%;
         width: 100%;
         overflow: hidden;
     }
@@ -626,6 +625,10 @@ img {
         border-right: 0;
     }
 
+    .toolkit-select .toolkit-select--wrapper {
+        width: 100%;
+    }
+
     .toolkit-button-group {
         display: flex;
         flex-wrap: wrap;