Increase test coverage cli.py

[JaGeo]

There are a few lines in the cli.py that are not yet covered by tests including

        if args.addtotaldos:
            dos_plotter.add_dos(dos=lobs_dos, label="Total DOS")

)
Maybe, we could address this.

[naik-aakash]

Yes, I will try to increase coverage of other modules too where I see we have less than 95% overall coverage