Delete Reboot Time and Cause line in aosw.rb

[feriniguez]

Reboot Time and Cause: AP rebooted Tue Jun 22 06:39:10 UTC 2021; CLI cmd at uptime 0D 0H 41M 48S: reload
Reboot Time and Cause: AP Reboot reason: BadPtr:0000000c PC:_raw_write_lock_bh+0x20/0x40 Wa

The above lines are examples of what we get with the "sh version" command. These lines change at every reboot of the device.
I don't think they're needed as part of the config backup.

Pre-Request Checklist

• Passes rubocop code analysis (try rubocop --auto-correct)
• Tests added or adapted (try rake test)
• Changes are reflected in the documentation
• User-visible changes appended to CHANGELOG.md

Description

[feriniguez]

Here a complete example of the show version in an Aruba 505H AP:

A-RU-BA-AP-1# sh version 
Aruba Operating System Software.
ArubaOS (MODEL: 505H), Version 8.7.1.4
Website: http://www.arubanetworks.com
(c) Copyright 2021 Hewlett Packard Enterprise Development LP.
Compiled on 2021-06-22 at 05:58:52 UTC (build 80581) by p4build
FIPS Mode :disabled

AP uptime is 1 hour 13 minutes 28 seconds
Reboot Time and Cause: AP rebooted Tue Jun 22 06:39:10 UTC 2021; CLI cmd at uptime 0D 0H 41M 48S: reload