chore: bump version 5.1.1 (#202)

Author: khvn26

setup.py

@@ -2,7 +2,7 @@
 
 setup(
     name="flagsmith-flag-engine",
-    version="5.1.0",
+    version="5.1.1",
     author="Flagsmith",
     author_email="[email protected]",
     packages=find_packages(include=["flag_engine", "flag_engine.*"]),