update links for account creation

CONTRIBUTING.md

@@ -24,16 +24,15 @@ followed by `make builddep`.
 
 ## How to submit a merge request
 
-To contribute code, you need an [MPI-SWS GitLab account][account] (use the
-"Register" tab).  Please send your MPI-SWS GitLab username to [Ralf Jung][jung]
-to unlock forks for your account.  Then you can fork the
+To contribute code, you need an MPI-SWS GitLab account as described on the
+[chat page](https://iris-project.org/chat.html).  Then you can fork the
 [Iris git repository][iris], make your changes in your fork, and create a merge
-request.
+request.  If forking fails with an error, please send your MPI-SWS GitLab
+username to [Ralf Jung][jung] to unlock forks for your account.
 
 Please do *not* use the master branch of your fork, that might confuse CI.  Use
 a feature branch instead.
 
-[account]: https://gitlab.mpi-sws.org/users/sign_in
 [jung]: https://gitlab.mpi-sws.org/jung
 [iris]: https://gitlab.mpi-sws.org/iris/iris
 

README.md

@@ -155,14 +155,12 @@ Contacting the developers:
 
 * Discussion about the Iris Coq development happens on the mailing list
   [iris-club@lists.mpi-sws.org](https://lists.mpi-sws.org/listinfo/iris-club)
-  and in the [Iris Chat](https://mattermost.mpi-sws.org/iris).  This is also the
-  right place to ask questions.  The chat requires an account at the
-  [MPI-SWS GitLab](https://gitlab.mpi-sws.org/users/sign_in): use the "Register"
-  tab, and then contact [Ralf](https://gitlab.mpi-sws.org/jung) to have your
-  account unlocked.
+  and in the [Iris Chat](https://iris-project.org/chat.html).  This is also the
+  right place to ask questions.
 * If you want to report a bug, please use the
-  [issue tracker](https://gitlab.mpi-sws.org/iris/iris/issues), which also
-  requires an MPI-SWS GitLab account.
+  [issue tracker](https://gitlab.mpi-sws.org/iris/iris/issues), which requires
+  an MPI-SWS GitLab account. The [chat page](https://iris-project.org/chat.html)
+  describes how to create such an account.
 * To contribute to Iris itself, see the [contribution guide](CONTRIBUTING.md).
 
 Miscellaneous: