appveyor: fix broken build

pquentin · pquentin · commit f331ec49a9b1 · 2019-11-12T11:07:32.000+04:00
diff --git a/dev-requirements.txt b/dev-requirements.txt
@@ -18,5 +18,7 @@ gcp-devrel-py-tools
 
 # optional dependencies, only intended for use with Python 3.5+
 trio==0.3.0; python_version >= "3.5"
+# https://github.com/mhammond/pywin32/issues/1439
+pywin32!=226; python_version >= "3.5" and os_name == 'nt'
 twisted[tls]==19.2.0; python_version >= "3.5" and os_name != 'nt'
 twisted[tls,windows_platform]==19.2.0; python_version >= "3.5" and os_name == 'nt'
