Make creating dev data be a command

Currently you need to set an environment variable and then run the
normal flask run command. It can be difficult to remember the
environment variable and if you forget to remove it then we recreate
the data. Making it a command means it is shown in flask --help and you
can run it directly and it will only create the dev data and exit.

api/main.py

@@ -1,5 +1,3 @@
-import os
-
 from factory import create_app
 
 app = create_app()
@@ -16,11 +14,14 @@ def teardown_request(*args, **kwargs):
     db.session.remove()
 
 
-if "Development" in os.environ.get("SERVER_SOFTWARE", ""):
+@app.cli.command("create-dev-data")
+def create_dev_data_entrypoint():
+    """Add development data to the configured database"""
     from database import db
     from tests.conftest import create_dev_data
 
     create_dev_data(db.session)
 
+
 if __name__ == "__main__":
     app.run()