Add twine and towncrier as dev dependencies (#11233)

We don't pin them as we execute them as commands, rather than use them
as libs.

1 files changed, 3 insertions, 0 deletions

diff --git a/setup.py b/setup.py
index 220084a49d..345cff09c3 100755
--- a/setup.py
+++ b/setup.py
@@ -132,6 +132,9 @@ CONDITIONAL_REQUIREMENTS["dev"] = (
         "GitPython==3.1.14",
         "commonmark==0.9.1",
         "pygithub==1.55",
+        # The following are executed as commands by the release script.
+        "twine",
+        "towncrier",
     ]
 )