[Comms handbook] Add ready-for-review deadline reminder template

[aibarbetta]

What type of PR is this:

/kind documentation

What this PR does / why we need it:

Adds a message template to remind Feature Blog authors of the ready-for-review deadline on week 13

Which issue(s) this PR fixes:

Special notes for your reviewer:

[aibarbetta]

/assign @rytswd

[rytswd]

Thanks @aibarbetta! It would probably be the best if you can also fix up the version tag to start with "v" prefix -- but that could be in another PR 👍

[rytswd]

/lgtm

[rytswd]

/lgtm /approve

Though I don't think I have entitlement for the merge

[Vyom-Yadav]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: aibarbetta, rytswd, Vyom-Yadav

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:

• ~~release-team/role-handbooks/communications/OWNERS~~ [Vyom-Yadav]

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