Update the SVG of default user avatar so it does not use ids and masks

to avoid the issue of the default avatar being not displayed because it shares the same id with other svg.

__tests__/shared/components/__snapshots__/Avatar.jsx.snap

@@ -7,45 +7,17 @@ exports[`Snapshots 1`] = `
   viewBox="0 0 141 141"
   width="141"
   xmlns="http://www.w3.org/2000/svg"
-  xmlnsXlink="http://www.w3.org/1999/xlink"
 >
   <title>
     ico-user-default
   </title>
-  <defs>
-    <rect
-      height="140"
-      id="a"
-      rx="306"
-      width="140"
-      x=".8"
-      y=".5"
-    />
-  </defs>
-  <g
-    fill="none"
+  <path
+    d="M71 35c-17.304 0-31.334 14.071-31.334 31.428v7.857c0 11.307 6.017 21.144 14.955 26.684-11.399 4.27-22.608 13.347-27.728 24.111C38.886 134.728 54.14 140.5 70.8 140.5c16.792 0 32.16-5.862 44.197-15.648-5.17-10.664-16.3-19.643-27.611-23.883 8.93-5.54 14.947-15.377 14.947-26.684v-7.857C102.334 49.07 88.304 35 71 35z"
+    fill="#A3A3AE"
     fillRule="evenodd"
-  >
-    <mask
-      fill="#fff"
-      id="b"
-    >
-      <use
-        xlinkHref="#a"
-      />
-    </mask>
-    <use
-      fill="#F0F0F0"
-      xlinkHref="#a"
-    />
-    <path
-      d="M118 137.143c0 4.345-3.501 7.857-7.833 7.857H31.833C27.51 145 24 141.488 24 137.143c0-15.714 15.142-30.376 30.62-36.174-8.937-5.54-14.953-15.377-14.953-26.683v-7.857C39.667 49.072 53.697 35 71 35c17.304 0 31.333 14.072 31.333 31.429v7.857c0 11.306-6.016 21.143-14.946 26.683 15.471 5.798 30.613 20.46 30.613 36.174z"
-      fill="#A3A3AE"
-      mask="url(#b)"
-      opacity=".2"
-      stroke="#A3A3AE"
-      strokeWidth="3"
-    />
-  </g>
+    opacity=".2"
+    stroke="#A3A3AE"
+    strokeWidth="3"
+  />
 </svg>
 `;