docs: update .all-contributorsrc [skip ci]

allcontributors[bot] · eakirtas · commit e95a38875d8a · 2021-07-06T12:29:49.000+03:00
diff --git a/.all-contributorsrc b/.all-contributorsrc
@@ -49,6 +49,17 @@
       "contributions": [
         "bug"
       ]
+    },
+    {
+      "login": "NickKok",
+      "name": "Nikolaos Kokkinis-Ntrenis",
+      "avatar_url": "https://avatars.githubusercontent.com/u/8222731?v=4",
+      "profile": "https://nickkok.github.io/my-website/",
+      "contributions": [
+        "code",
+        "doc",
+        "ideas"
+      ]
     }
   ],
   "contributorsPerLine": 7,
