Renew license online if license file not passed

[anjalshireesh]

Description

If the license key file is not passed as argument to the license update command, and if the cluster is registered, automatically renew the license and update it.

Motivation and Context

Ability to pull latest (renewed) license from mc

How to test this PR?

• Create a custom account on subnet with the subscription end date set to 1 month from now
• Register a cluster in this account using mc license register {alias}
• Check license info using mc license info {alias} and note that the license expiry is same as subscription end date on subnet
• Extend the subscription of the account on subnet to 2 months from now
• Run mc license update {alias}
• Check license info using mc license info {alias} and verify that the license expiry has got extended correctly

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Optimization (provides speedup with no functional changes)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (If yes, please add commit-id or PR # here)
• Unit tests added/updated
• Internal documentation updated
• Create a documentation update request here