SDN-5474: network: Add ovnObservability flag to enable OVNObservability feature

[npinaeva]

with 100% sampling rate for all available features. More granular configuration will be available later with a separate CRD.

[openshift-ci-robot]

@npinaeva: This pull request references SDN-5474 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the story to target the "4.18.0" version, but no target version was set.

In response to [this](https://github.com/openshift/api/pull/2092): >with 100% sampling rate for all available features. >More granular configuration will be available later with a separate CRD. Instructions for interacting with me using PR comments are available [here](https://prow.ci.openshift.org/command-help?repo=openshift%2Fapi). If you have questions or suggestions related to my behavior, please file an issue against the [openshift-eng/jira-lifecycle-plugin](https://github.com/openshift-eng/jira-lifecycle-plugin/issues/new) repository.

[openshift-ci[bot]]

Hello @npinaeva! Some important instructions when contributing to openshift/api: API design plays an important part in the user experience of OpenShift and as such API PRs are subject to a high level of scrutiny to ensure they follow our best practices. If you haven't already done so, please review the OpenShift API Conventions and ensure that your proposed changes are compliant. Following these conventions will help expedite the api review process for your PR.

[openshift-ci[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: npinaeva Once this PR has been reviewed and has the lgtm label, please assign derekwaynecarr for approval. For more information see the Kubernetes Code Review Process.

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[openshift-ci[bot]]

@npinaeva: The following tests 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/integration	45fda34d78db73d99aa9afe324136f8a13deb810	link	true	/test integration
ci/prow/verify-crd-schema	45fda34d78db73d99aa9afe324136f8a13deb810	link	true	/test verify-crd-schema

Full PR test history. Your PR dashboard.

Instructions for interacting with me using PR comments are available [here](https://git.k8s.io/community/contributors/guide/pull-requests.md). If you have questions or suggestions related to my behavior, please file an issue against the [kubernetes-sigs/prow](https://github.com/kubernetes-sigs/prow/issues/new?title=Prow%20issue:) repository. I understand the commands that are listed [here](https://go.k8s.io/bot-commands).

[npinaeva]

/hold waiting for final decision on the release