Release of version 0.9.0

[sesheta]

Hey, @LaVLaS!

Opening this PR to create a release in a backwards compatible manner.

Related: #78

Changelog:
### Features
* Add lavlas to thoth maintainers (#77)
* enable thoth-bot kebechet to handle release changelogs (#72)

[sefkhet-abwy]

This is an auto-approve of an auto-PR.

[openshift-ci-robot]

@sefkhet-abwy[bot]: changing LGTM is restricted to collaborators

In response to this:

This is an auto-approve of an auto-PR.

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.

[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: sefkhet-abwy[bot], sesheta
To complete the pull request process, please assign lavlas after the PR has been reviewed.
You can assign the PR to them by writing /assign @lavlas in a comment when ready.

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[openshift-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

Approval requirements bypassed by manually added approval.

This pull-request has been approved by: sefkhet-abwy[bot], sesheta

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

Approvers can indicate their approval by writing /approve in a comment
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[vpavlin]

/lgtm