Automatic merge from submit-queue
IPv6 support for hexCIDR()
Includes these changes:
- Modified so that IPv6 CIDRs can be converted correctly.
- Added test cases for IPv6 addresses.
- Split UTs for hexCIDR() and asciiCIDR() so that masking can be tested.
- Add UTs for failure cases.
Note: Some code that calls hexCIDR() builds a CIDR from the pod IP string
and the concatenation of "/32". These should, in the future, use "128",
if/when the pod IP is IPv6. Not addressed as part of this commit.
**What this PR does / why we need it**:
**Which issue this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close that issue when PR gets merged)*: fixes#45906
**Special notes for your reviewer**:
**Release note**:
```release-noteNONE
```