Allow disabling IPv6 for Hubble UI

[xmudrii]

What this PR does / why we need it:

This PR introduces a new parameter for the Cilium addon called HubbleIPv6. This parameter is used to enable/disable Hubble UI listening on an IPv6 interface. By default, the value of this parameter is true which means that Hubble UI is listening on an IPv6 interface, and it can be set to false to disable listening on IPv6.

Example:

...
addons:
  enable: true
  addons:
    - name: cni-cilium
      params:
        HubbleIPv6: "true"

Which issue(s) this PR fixes:
Fixes #2446

What type of PR is this?

/kind feature

Does this PR introduce a user-facing change? Then add your Release Note here:

Add a new addon parameter called `HubbleIPv6` (`true`/`false`, default: `true`) for Cilium CNI used to enable/disable Hubble UI listening on an IPv6 interface

Documentation:

NONE

[kron4eg]

/lgtm
/approve

[kubermatic-bot]

LGTM label has been added.

Git tree hash: 673c038ecd3330f5e0d2c8b412a6d32a633d9e32

[kubermatic-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kron4eg

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• OWNERS [kron4eg]

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[xmudrii]

/cherrypick release/v1.5

[xmudrii]

/cherrypick release/v1.4

[kubermatic-bot]

@xmudrii: new pull request created: #2451

In response to this:

/cherrypick release/v1.5

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[kubermatic-bot]

@xmudrii: #2448 failed to apply on top of branch "release/v1.4":

Applying: Allow disabling IPv6 for Hubble UI
Using index info to reconstruct a base tree...
M	addons/cni-cilium/cilium.yaml
Falling back to patching base and 3-way merge...
Auto-merging addons/cni-cilium/cilium.yaml
CONFLICT (content): Merge conflict in addons/cni-cilium/cilium.yaml
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0001 Allow disabling IPv6 for Hubble UI
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

In response to this:

/cherrypick release/v1.4

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.