docs: update changed contributor username (#817)

.all-contributorsrc

@@ -642,10 +642,10 @@
       ]
     },
     {
-      "login": "x-jokay",
+      "login": "jokay",
       "name": "D. Domig",
       "avatar_url": "https://avatars0.githubusercontent.com/u/18613935?v=4",
-      "profile": "https://github.com/x-jokay",
+      "profile": "https://github.com/jokay",
       "contributions": [
         "doc"
       ]

README.md

@@ -128,7 +128,7 @@ Thanks goes to these wonderful people ([emoji key](https://allcontributors.org/d
     <td align="center"><a href="https://github.com/MihailITPlace"><img src="https://avatars2.githubusercontent.com/u/28401551?v=4?s=100" width="100px;" alt=""/><br /><sub><b>MihailITPlace</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=MihailITPlace" title="Code">💻</a></td>
     <td align="center"><a href="https://github.com/bugficks"><img src="https://avatars1.githubusercontent.com/u/2992895?v=4?s=100" width="100px;" alt=""/><br /><sub><b>bugficks</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=bugficks" title="Code">💻</a> <a href="https://github.com/containrrr/watchtower/commits?author=bugficks" title="Documentation">📖</a></td>
     <td align="center"><a href="https://github.com/MichaelSp"><img src="https://avatars0.githubusercontent.com/u/448282?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Michael</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=MichaelSp" title="Code">💻</a></td>
-    <td align="center"><a href="https://github.com/x-jokay"><img src="https://avatars0.githubusercontent.com/u/18613935?v=4?s=100" width="100px;" alt=""/><br /><sub><b>D. Domig</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=x-jokay" title="Documentation">📖</a></td>
+    <td align="center"><a href="https://github.com/jokay"><img src="https://avatars0.githubusercontent.com/u/18613935?v=4?s=100" width="100px;" alt=""/><br /><sub><b>D. Domig</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=jokay" title="Documentation">📖</a></td>
     <td align="center"><a href="https://maxwells-daemon.io"><img src="https://avatars1.githubusercontent.com/u/260084?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Ben Osheroff</b></sub></a><br /><a href="https://github.com/containrrr/watchtower/commits?author=osheroff" title="Code">💻</a></td>
   </tr>
   <tr>