Add composite field behaviour change to HISTORY

Author: timsavage

HISTORY

@@ -2,6 +2,10 @@
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 - Add ValidationErrorCollection helper for simplifying collection of errors in custom validation code.
+- Change behaviour of to_python method on a CompositeField to not do a full clean.
+  This is not required as this should be completed during the validation stage.
+  This prevents double validation and solves the issue of resources not being populated at all if
+  any contained field contains an error.
 
 2.4
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