[stable/prometheus-adapter] Add myself to OWNERS

[steven-sheehy]

What this PR does / why we need it:

There's a lot of open PRs for this chart that aren't being approved. After the call for maintainers, I thought I might offer up my help for this chart. Adds an OWNERS file, adds myself to it and existing chart maintainer from Chart.yaml

Which issue this PR fixes

See #13867

Special notes for your reviewer:

I didn't put my email in the Chart.yaml since I've been getting a lot of spam due to it being in other charts that I maintain. Hope that's OK.

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• DCO signed
• Chart Version bumped
• Variables are documented in the README.md
• title of the PR contains starts with chart name e.g. [stable/chart]

[steven-sheehy]

/assign @maorfr
/assign @MattiasGees

[k8s-ci-robot]

@steven-sheehy: GitHub didn't allow me to assign the following users: mattiasgees.

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For more information please see the contributor guide

In response to this:

/assign @maorfr
/assign @MattiasGees

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.

[maorfr]

/cc @MattiasGees
would you like to be added as an OWNER to this chart?

[k8s-ci-robot]

@maorfr: GitHub didn't allow me to request PR reviews from the following users: MattiasGees.

Note that only helm members and repo collaborators can review this PR, and authors cannot review their own PRs.

In response to this:

/cc @MattiasGees
would you like to be added as an OWNER to this chart?

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.

[maorfr]

/lgtm

welcome @steven-sheehy !

[steven-sheehy]

@maorfr Mind lgtm it again?

[maorfr]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: maorfr, steven-sheehy

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 [maorfr]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[steven-sheehy]

/retest