Chore: Bump CNI/ CNS version from v1.6.0 to v1.6.3.

[sivakami-projects]

What type of PR is this?

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

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Release note:

none

[coveralls]

Pull Request Test Coverage Report for Build 10461414531

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 71.069%

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Totals
Change from base Build 10458929293:	0.0%
Covered Lines:	2572
Relevant Lines:	3619

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💛 - Coveralls

[rbtr]

cc @QxBytes

[QxBytes]

Currently the 1.5.32 cni/cns version is still rolling out and so if we remove the 1.5.28 cni/cns version existing clusters/clusters in regions which haven't been upgraded may be affected.

[QxBytes]

according to cameron, VHD changes will likely take 1-2 weeks before reaching aks rp, so removing v1.5.28 while v1.5.32 is currently rolling out should be fine.