Add missing dependency.

The `odk` script requires the `requests` module (used by the `setup`
command to download online files). It is automatically installed as an
indirect dependency of several packages required by the `workflows`
extra, but we don't want to have to install those extra packages just to
run the seeding script.

Author: gouttegd

pyproject.toml

@@ -23,6 +23,7 @@ dependencies = [
     "defusedxml",
     "jinja2",
     "pyyaml",
+    "requests"
 ]
 
 [project.urls]