filesystem: T3946: GPT table fix after drive resize on Azure

[andriiandrieiev]

Change Summary

It was found that disk extension on Azure brakes GPT table

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Code style update (formatting, renaming)
• Refactoring (no functional changes)
• Migration from an old Vyatta component to vyos-1x, please link to related PR inside obsoleted component
• Other (please describe):

Related Task(s)

• https://phabricator.vyos.net/T3946

Component(s) name

Proposed changes

Add to parted utility inline directives that will fix GPT table before a resizing attempt

How to test

On Azure:

1. Deallocate a VM
2. Extend a VM disk
3. Start VM
4. Enable root-partition-auto-resize.service

configure
set system option root-partition-auto-resize
commit
save
exit

5. Do system reboot
6. Check partition size and FS size:

lsblk
df -h

Instead of steps 4 and 5 it's possible just to run once from op mode:

force root-partition-auto-resize

Checklist:

• I have read the CONTRIBUTING document
• I have linked this PR to one or more Phabricator Task(s)
• I have run the components SMOKETESTS if applicable
• My commit headlines contain a valid Task id
• My change requires a change to the documentation
• I have updated the documentation accordingly