Handle paginated results in e2e-upgrade-functests

[0xFelix]

Is this a BUG REPORT or FEATURE REQUEST?:

Uncomment only one, leave it on its own line:

/kind bug
/kind enhancement

What happened:

https://github.com/kubevirt/ssp-operator/blob/54285313efecb017c47744dda5b666bdfd4a1c56/automation/e2e-upgrade-functests/run.sh#L24C20-L24C86

This scripts queries for release branches and by default there is a limit of 30 items per page.
Since dependabot started creating a lot of branches, the branches we are looking for are no longer returned on page one. This resulted in the CI failing.

See #792

What you expected to happen:

The script should handle paginated results, see https://docs.github.com/en/rest/branches/branches?apiVersion=2022-11-28#list-branches--parameters

How to reproduce it:

Anything else we need to know?:

Environment:

• KubeVirt version (use virtctl version):
• Kubernetes version (use kubectl version):
• SSP Operator version:
• VM or VMI specifications:
• Cloud provider or hardware configuration:
• OS (e.g. from /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Others:

[kubevirt-bot]

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[akrejcir]

/remove-lifecycle stale