changed format of disk encryption set and assigned id to key vault key

[nileshgadgi]

what

• Changed format of disk encryption set in virtual machine.
• Reflected Disk encryption set id to key vault key resource to assign it with disk.

why

• Provide the justifications for the changes (e.g. business case).
• Describe why these changes were made (e.g. why do these commits fix the problem?)
• Use bullet points to be concise and to the point.

references

• Link to any supporting jira issues or helpful documentation to add some context (e.g. stackoverflow).
• Use closes #123, if this PR closes a Jira issue #123