Add arXiv icon (#1856)

Closes  #1854

_data/simple-icons.json

@@ -235,6 +235,11 @@
             "hex": "13AFF0",
             "source": "https://www.artstation.com/about/logo"
         },
+        {
+            "title": "arXiv",
+            "hex": "B31B1B",
+            "source": "https://static.arxiv.org/static/base/0.15.2/images/arxiv-logo-web.svg"
+        },
         {
             "title": "Asana",
             "hex": "273347",

icons/arxiv.svg

@@ -0,0 +1 @@
+<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>arXiv icon</title><path d="M20.7 15.404l-1.894-4.967h1.411l1.39 3.582 1.379-3.582h.96l-1.92 4.967zM16.298 9.6V8.48h1.34V9.6zm0 5.808v-4.971h1.34v4.967zm-6.965-.003l2.146-3.3L9.43 8.707h1.627l1.364 2.254L13.9 8.707h1.12l-2.046 3.156 2.126 3.537h-1.622l-1.45-2.4-1.557 2.4H9.333zm-3.346 0v-4.968h1.338v.937c.344-.7.875-1.051 1.585-1.051a1.401 1.401 0 01.248.026v1.194a1.6 1.6 0 00-.53-.102c-.537 0-.968.267-1.303.8v3.164zm-3.028-.536q-.664.65-1.437.65a1.473 1.473 0 01-1.06-.398 1.376 1.376 0 01-.406-1.03 1.45 1.45 0 01.659-1.271q.657-.447 1.884-.448h.355v-.453q0-.772-.88-.772a3.305 3.305 0 00-1.587.443v-.922a5.016 5.016 0 011.808-.345q1.953 0 1.951 1.55v2.206c0 .39.123.58.376.58a.8.8 0 00.174-.02l.032.751a2.745 2.745 0 01-.751.13c-.552 0-.902-.216-1.06-.65h-.054zm0-.72v-1.01h-.32c-.866 0-1.297.274-1.297.815a.64.64 0 00.64.648c.329.004.647-.15.977-.453z"/></svg>