Bump PolicyEngine UK to 2.28.1 (#2509)

Co-authored-by: PolicyEngine[bot] <hello@policyengine.org>

Author: nikhilwoodruff

changelog_entry.yaml

@@ -0,0 +1,4 @@
+- bump: patch
+  changes:
+    changed:
+    - Update PolicyEngine UK to 2.28.1

setup.py

@@ -24,7 +24,7 @@
         "policyengine_canada==0.96.2",
         "policyengine-ng==0.5.1",
         "policyengine-il==0.1.0",
-        "policyengine_uk==2.24.2",
+        "policyengine_uk==2.28.1",
         "policyengine_us==1.289.1",
         "policyengine_core>=3.16.6",
         "policyengine>=0.3.0",