Generated machine class name exceeds 63 character limitation

[EmoinLanyu]

How to categorize this issue?

/area control-plane
/kind bug
/priority normal
/platform alicloud

What happened:
Our user created a Shoot with multiple worker groups, some worker groups have failed to be created.
After investigation, we found that it is caused by exceed of length limitation of metadata.name for corresponding machineclass resources.
Our current way of naming it is shoot--(project_name)--(shoot_name)--(worker_group_name)--(region_id)--(worker_name). And Gardener limits:

• Project name: 10 chars
• Shoot name: 15 chars
• Worker group name: 15 chars

Worker name is auto generated and is usually 5 chars.
If we sum above numbers up (including word shoot and multiple -s), at minimum, there are only 3 chars left for region_id.

What you expected to happen:
Whatever users name their projects, shoots, worker groups, workers should not block the workers from being successfully created.

How to reproduce it (as minimally and precisely as possible):
Create a worker in a worker group whose name is maximum char length, in a shoot whose name is maximum char length, in a project whose name is maximum char length.

Anything else we need to know?:
Currently we see this issue on AliCloud. But I suppose it is the same across all cloud providers.

Environment:
AliCloud Canary

• Gardener version (if relevant):
• Extension version: <= 1.19.0
• Kubernetes version (use kubectl version):
• Cloud provider or hardware configuration:
• Others: