[Python Connexion Servers] BUGFIX: handle . in package names

Created by: cognifloyd

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Description of the PR

For python connexion servers: This fixes adding supporting files to packages that have a '.'.

If the controllersPackage or modelsPackage has a '.' (eg to put the controllers and/or models in a subpackage of the invokerPackage), supporting controller and models were ending up in directories that included the period instead of converting the periods to file separators.