CCM will remove the space behind the tag, may cause issue on Kubenet AKS cluster

[gsxmax]

What happened:

When using a tag like "Null "(Null+space) on kubenet AKS, if we do an action like scale up the nodepool, we will hit "InvalidReservedTagValue" error while updating the routetable.

What you expected to happen:

Able to update the routetable.

How to reproduce it (as minimally and precisely as possible):

• Add tag "test:Null "(test:Null+space) on kubenet AKS cluster.
• Scale up the nodepool

Anything else we need to know?:

Environment:

• Kubernetes version (use kubectl version): 1.29.7 (Any AKS version should be able to reproduce this)
• Cloud provider or hardware configuration:
• OS (e.g: cat /etc/os-release): Ubuntu 22.04.4 LTS
• Kernel (e.g. uname -a): Linux aks-agentpool-26712724-vmss00000I 5.15.0-1071-azure Setup artifacts volume for runner #80-Ubuntu SMP Tue Aug
  6 19:27:32 UTC 2024 x86_64 x86_64 x86_64 GNU/Linux
• Install tools: None
• Network plugin and version (if this is a network-related bug): Kubenet
• Others: