[release-1.25] fix: update resources in batches asynchonously

[k8s-infra-cherrypick-robot]

This is an automated cherry-pick of #3757

/assign nilo19

fix: update resources in batches asynchonously

A regression was introduced by #1687 where the behavior of updating resources in batches changes from sending requests asynchonously to synchonously. This would lead to latencies when updating vmss vms, especially when the cluster size is huge. This unexpected change is reverted in this fix.

[linux-foundation-easycla]

• ✅ login: nilo19 / name: Qi Ni (1119eb9)
• ❌ The commit (1119eb9). This user is missing the User's ID, preventing the EasyCLA check. Consult GitHub Help to resolve.For further assistance with EasyCLA, please submit a support request ticket.

[k8s-ci-robot]

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[lzhecheng]

/kind bug
/lgtm

[lzhecheng]

easycla failure is not related. Merging.