Add support for IPv6 in connectivity tests

[lel-amri]

As of today, values specified in options --external-ip and --external-other-ip are assumed to be IPv4 addresses in several places in the code. This cause some tests to fail even when a proper IPv6 configuration is specified with options --external-cidr, --external-ip, --external-other-ip and --external-target. This pull request remove the assumptions that these options holds IPv4 addresses.

[maintainer-s-little-helper[bot]]

Commit 0bda11d9cdd5bb020813ccbfd5bc8ed6a03685c7 does not match "Signed-off-by".

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[lel-amri]

Hello @christarazi and @doniacld, thanks for your review and sorry for the delay.

I'd like to write some tests to cover the new code paths but I'm unsure how to proceed. Do you have some pointers to put me on the right track?

Also I'm unsure whether the IsIPv4, IsIPv6 and EnsureIPv6InBrackets are placed in the right file. I was looking for somewhere to place common helper functions and ended up using a file named common as close as possible to the file actually using the functions, but it seems to me that connectivity/tests/common.go is intended to contain common connectivity testing code.

[maintainer-s-little-helper[bot]]

Commit 93bd37ec8d8a65a18c612dbd1ee3e66b24367a64 does not match "Signed-off-by".

Please follow instructions provided in https://docs.cilium.io/en/stable/contributing/development/contributing_guide/#developer-s-certificate-of-origin

[github-actions[bot]]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[github-actions[bot]]

This pull request has not seen any activity since it was marked stale. Closing.