epoll-shim: temporarily use my fork

The current version of epoll-shim does not work as a purecap library.
Use my fork until jiixyj/epoll-shim#36 has
been merged.

pycheribuild/projects/cross/wayland.py

@@ -39,7 +39,9 @@
 
 class BuildEPollShim(CrossCompileCMakeProject):
     target = "epoll-shim"
-    repository = GitRepository("https://github.com/jiixyj/epoll-shim")
+    repository = GitRepository("https://github.com/jiixyj/epoll-shim",
+                               temporary_url_override="https://github.com/arichardson/epoll-shim",
+                               url_override_reason="https://github.com/jiixyj/epoll-shim/pull/36")
     supported_architectures = CompilationTargets.ALL_FREEBSD_AND_CHERIBSD_TARGETS + [CompilationTargets.NATIVE]
 
     def configure(self, **kwargs):