[PATCH] docs: pin mistune version due to breakage

[You-Sheng Yang]

mistune made a new release which breaks API referenced by Sphinx v4.3.1.

Closes: #442
Signed-off-by: You-Sheng Yang <vicamo at gmail.com>
---
 docs/requirements.txt | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/requirements.txt b/docs/requirements.txt
index f17cb78..7668b88 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -3,3 +3,5 @@ reno>=3.4.0
 sphinx-rtd-theme~=1.0
 jinja2~=3.0
 sphinxcontrib-openapi~=0.7.0
+# See https://github.com/getpatchwork/patchwork/issues/442
+mistune<2.0.0
-- 
2.32.0