Correct cloudevents dependency to allow 1.11.0

Python 3.7 is no longer supported so don't allow versions prior to
1.11.0 but allow 1.11.0 as Python 3.8 is still supported by the
framework.

Author: maemayve

pyproject.toml

@@ -27,7 +27,7 @@ dependencies = [
   "click>=7.0,<9.0",
   "watchdog>=1.0.0",
   "gunicorn>=22.0.0; platform_system!='Windows'",
-  "cloudevents>=1.12.0,<=1.12.0",                   # Must support python 3.7
+  "cloudevents>=1.11.0,<=1.12.0",                   # Must support python 3.8
   "Werkzeug>=0.14,<4.0.0",
   "starlette>=0.37.0,<1.0.0; python_version>='3.8'",
   "uvicorn>=0.18.0,<1.0.0; python_version>='3.8'",