update getParameters when rebuilding model

[arun3688]

Purpose

This PR fixes the bug in getParameters() with new values set by users using setParameters() API. after rebuilding the model using buildModel().

Example

from OMPython import ModelicaSystem
omc= ModelicaSystem("Test.mo", "Test.Example")
omc.getParameters()
## use the setParameters() API 
omc.setParameters("c=9")
omc.buildModel
omc.simulate()
c = omc.getParameters("c")

output

c = 9