Fix release notes generated for rc.0 tag

[chandankumar4]

What steps did you take and what happened?

Release noted generated for v1.10.0-rc.0 is generated by comparing the changes between tags/v1.9.0 and heads/main But it should be between tags/v1.9.0 and heads/release-1.10.

Adding branch here fixed the issue, for ex: --branch release-1.10. So the branch name should be dynamics, probably we can use variable RELEASE_TAG to generate release branch.

What did you expect to happen?

It should Computing diff between tags/v1.9.0 and heads/release-1.10

Cluster API version

v1.10

Kubernetes version

No response

Anything else you would like to add?

No response

Label(s) to be applied

/kind bug
One or more /area label. See https://github.com/kubernetes-sigs/cluster-api/labels?q=area for the list of labels.

[chrischdi]

/help

[k8s-ci-robot]

@chrischdi:
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[neoaggelos]

/assign

[chandankumar4]

I have unassigned this issue, as heard no response on slack, let me know if you have made any progress on this. Thanks
/unassign @neoaggelos