Add install task to tasks, for good measure

tasks.py

@@ -10,3 +10,7 @@ def run(c, port=8080, host='127.0.0.1'):
         f'poetry run python -m flask run -p {port} -h {host}',
         env={'FLASK_APP': 'lc/main.py'},
     )
+
+@task
+def install(c):
+    c.run('poetry install')