Add missing required library in pyproject.toml

pyproject.toml

@@ -14,7 +14,7 @@
   "Framework :: Odoo :: 13.0",
   "License :: OSI Approved :: GNU Affero General Public License v3"
 ]
-dependencies = ["odoo ==13.0.*"]
+dependencies = ["odoo ==13.0.*", "freezegun >=1.2.1"]
 
 [project.optional-dependencies]
 doc = ["sphinx", "sphinx-odoo-autodoc", "odoo-scripts"]