Improve release note layout: make it shorter with collapsable sections

[jotak]

I also edited the latest release with this format, so you can take a look if you want: https://github.com/netobserv/network-observability-operator/releases/tag/1.8.0-community

[openshift-ci]

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[openshift-ci]

@jotak: The following test failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-operator	7a384cc	link	false	/test e2e-operator

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