Code review comment for ~dashmage/charm-sysconfig:bug-2012581/inherit-existing-kernel-params

After discussing with @nobuto, the real issue faced is not that the MAAS console parameters are being overwritten.

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the original issue was that even if the machine already had ttyS0 and tty, charm added those additionally and it triggered a reboot required flag

as long as the reboot required flag is not triggered, I'm happy with any solutions
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The charm will certainly trigger a reboot notification at the time of deployment since the template file has minor changes from the original config file on the unit. But this only happens at the time of initial deployment of the charm. Could a possible solution be to have the charm run the `clear-notification` action as part of the install hook handler since the notification is a false positive?

In case the charm does need to support a way to prevent overwriting the MAAS kernel parameters, I've listed down some possible solutions and my proposal in this document here: https://docs.google.com/document/d/19sB_LqBY5xFL0-8JDc1RzgOzQh8quwa3NSsXQIbkfj0/edit?usp=sharing