remove line that recreates previousVersion for no reason.

The variable previousVersion stored an array of the keys belonging to the dictionary undoMap. This last line regenerated this array for no reason, since previousVersion is a local variable and is not mutated inside the message's body.

src/Glorp/ObjectTransaction.class.st

@@ -150,8 +150,7 @@ ObjectTransaction >> registeredObjectsDo: aBlock [
 			newAdditions := OrderedCollection new.
 			undoMap
 				keysDo:
-					[:eachKey | (previousVersion includes: eachKey) ifFalse: [newAdditions add: eachKey]].
-			newAdditions isEmpty ifFalse: [previousVersion := undoMap keys]]
+					[:eachKey | (previousVersion includes: eachKey) ifFalse: [newAdditions add: eachKey]]]
 ]
 
 { #category : #registering }