rpk: license warning text changes.

[r-vasquez]

This PR adds a new warning message for expired enterprise licenses and modifies existing ones to display the days left until the license expires.

Examples:

Note: your TRIAL license will expire in 9 days. To request a license, please visit https://redpanda.com/upgrade.
To try Redpanda Enterprise for 30 days, visit https://redpanda.com/try-enterprise. For more information, see
https://docs.redpanda.com/current/get-started/licenses/#redpanda-enterprise-edition

LICENSE INFORMATION
===================
License status:     valid
License violation:  false
Organization:       Devex
Type:               free_trial
Expires:            Dec 2 2024

$ rpk cluster health

WARNING: your ENTERPRISE license has expired. The following Enterprise features are being used in
your Redpanda cluster: [partition_auto_balancing_continuous]. These features require a license.
To request a new license, please visit https://support.redpanda.com. For more information, see
https://docs.redpanda.com/current/get-started/licenses/#redpanda-enterprise-edition

CLUSTER HEALTH OVERVIEW
=======================
Healthy:                          true
Unhealthy reasons:                []
Controller ID:                    0
All nodes:                        [0]
Nodes down:                       []
Leaderless partitions (0):        []
Under-replicated partitions (0):  []

Backports Required

• [ ] none - not a bug fix
• [ ] none - this is a backport
• [ ] none - issue does not exist in previous branches
• [ ] none - papercut/not impactful enough to backport
• [X] v24.3.x
• [ ] v24.2.x
• [ ] v24.1.x

Release Notes

• none

[mattschumpert]

lgtm

[r-vasquez]

Unrelated build-bazel error in https://buildkite.com/redpanda/redpanda/builds/58613#019355f3-cb20-47d4-aec7-b2b3fa1203a8

Is being fixed in https://github.com/redpanda-data/redpanda/pull/24222/commits/3431bfb54b081c1916a6191ae056638d1396e435

[vbotbuildovich]

/backport v24.3.x