update: Remove node-speakers (#2283)

The node-speakers page is problematic for several reasons. Remove it.

Author: Trott

locale/ar/get-involved/node-speakers.md

@@ -134,10 +134,6 @@
     "node-events": {
       "link": "get-involved/node-events",
       "text": "Node.js فعاليات"
-    },
-    "node-speakers": {
-      "link": "get-involved/node-speakers",
-      "text": "متحدثو الـ Node.js"
     }
   },
   "security": {

locale/ar/site.json

@@ -135,10 +135,6 @@
     "node-events": {
       "link": "get-involved/node-events",
       "text": "Node.js Events"
-    },
-    "node-speakers": {
-      "link": "get-involved/node-speakers",
-      "text": "Node.js Speakers"
     }
   },
   "security": {