Add the possibility to specify a custom name for network scenario configuration file from the Python API

[tcaiazzi]

Currently, the LabParser.parse() method only accepts a configuration file called lab.conf.

https://github.com/KatharaFramework/Kathara/blob/aaa0b721cdc1e4ec44a09841e99448313e315e7b/src/Kathara/parser/netkit/LabParser.py#L13-L87

Adding the possibility to specify the name of the configuration file will improve flexibility.