Correct typo

src/main/scala/leon/datagen/NaiveDataGen.scala

src/main/scala/leon/datagen/VanuatooDataGen.scala

src/main/scala/leon/purescala/Definitions.scala

src/main/scala/leon/purescala/ExprOps.scala

src/main/scala/leon/purescala/MethodLifting.scala

src/main/scala/leon/purescala/Types.scala

src/main/scala/leon/solvers/ADTManager.scala

src/main/scala/leon/solvers/smtlib/SMTLIBSolver.scala

src/main/scala/leon/solvers/z3/AbstractZ3Solver.scala

src/main/scala/leon/synthesis/PartialSolution.scala

src/main/scala/leon/synthesis/graph/DotGenerator.scala

src/main/scala/leon/synthesis/graph/Graph.scala

src/main/scala/leon/synthesis/graph/Search.scala

src/main/scala/leon/synthesis/rules/ADTInduction.scala

src/main/scala/leon/synthesis/rules/ADTLongInduction.scala

src/main/scala/leon/synthesis/rules/ADTSplit.scala

src/main/scala/leon/synthesis/utils/ExpressionGrammar.scala

src/main/scala/leon/termination/ChainComparator.scala

src/main/scala/leon/termination/StructuralSize.scala

src/main/scala/leon/utils/TypingPhase.scala