Documentation: Recommend using the latest schema version (v11)

[PabloCastellano]

What this PR does / why we need it:

According to the architecture docs, latest schema version is v10 v11. However the documentation mentions only v9 in the examples.

This PR updates the docs and default values accordingly.

Checklist

• Documentation added
• Tests updated

[claassistantio]

All committers have signed the CLA.

[slim-bean]

Hey @PabloCastellano thank you for your PR.

The current schema for Loki is actually v11, however we have held off on updating the helm chart because it will break current users, when rolling out a new schema you need to add a new entry to the list of schemas with a future dated start date.

We think it might be possible to do this dynamically however haven't had a chance to figure this out yet. Basically anyone who is doing a new install would want v11 with a date prior to today, anyone doing an upgrade would need a new schema entry with v11 future dated for at least tomorrow.

[PabloCastellano]

Hi @slim-bean, is it OK if I change the PR then to mention v11 and remove the changes related to the helm chart?

Edit: done already

[codecov-io]

Codecov Report

Merging #1608 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1608   +/-   ##
=======================================
  Coverage   60.69%   60.69%           
=======================================
  Files         107      107           
  Lines        8075     8075           
=======================================
  Hits         4901     4901           
  Misses       2787     2787           
  Partials      387      387

[cyriltovena]

LGTM