Incremented minimal z3 version required for the z3LpSolver to 4.5.0 as the optimizer in 4.4.1 yielded wrong results in the tests

resources/3rdparty/CMakeLists.txt

@@ -141,7 +141,7 @@ if(Z3_FOUND)
                 OUTPUT_STRIP_TRAILING_WHITESPACE)
         if (z3_version_output MATCHES "([0-9]*\\.[0-9]*\\.[0-9]*)")
             set(Z3_VERSION "${CMAKE_MATCH_1}")
-            if(NOT "${Z3_VERSION}" VERSION_LESS "4.4.1")
+            if(NOT "${Z3_VERSION}" VERSION_LESS "4.5.0")
                 set(STORM_HAVE_Z3_OPTIMIZE ON)
             endif()
         endif()