Calico: use --allow-version-mismatch in calicoctl.sh to allow upgrades

[cristicalin]

What type of PR is this?

/kind bug

What this PR does / why we need it:
Calico 3.20 introduced a feature to protect clusters from being modified by incompatible calicoctl versions. This has an impact in upgrading Calico from earlier versions to 3.20.
The change proposed here modifies the wrapper used (calicoctl.sh) which in effect reverts back to the old behavior. An alternative would be to modify the calls to calicoctl.sh from our playbooks to add the --allow-version-mismatch flag.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:
I submit this change to get some feedback on the two approaches and I'm open to moving to the alternative if reviewers see fit.

Does this PR introduce a user-facing change?:

[k8s-ci-robot]

Hi @cristicalin. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

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.

[floryut]

/ok-to-test
Nice 👍

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cristicalin, floryut

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [floryut]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[oomichi]

/lgtm