add tkukushkin as a contributor for code, test, and bug (#944)

* update README.md [skip ci]

* update .all-contributorsrc [skip ci]

Co-authored-by: allcontributors[bot] <46447321+allcontributors[bot]@users.noreply.github.com>

Author: allcontributors[bot]

.all-contributorsrc

@@ -544,6 +544,17 @@
         "bug",
         "test"
       ]
+    },
+    {
+      "login": "tkukushkin",
+      "name": "Timofey Kukushkin",
+      "avatar_url": "https://avatars.githubusercontent.com/u/1482516?v=4",
+      "profile": "https://t.me/tkukushkin",
+      "contributions": [
+        "code",
+        "test",
+        "bug"
+      ]
     }
   ],
   "contributorsPerLine": 7,