Docs: example about using azure storage account as storage

[cbl315]

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #2907

Special notes for your reviewer:

Checklist

• Documentation added
• Tests updated

[CLAassistant]

All committers have signed the CLA.

[KMiller-Grafana]

Please make suggested changes. Then, this documentation addition will LGTM.

[KMiller-Grafana]

Thank you for making the changes. The docs LGTM now. Please take care of signing the CLA, such that we can merge these changes in.

[cbl315]

Thank you for making the changes. The docs LGTM now. Please take care of signing the CLA, such that we can merge these changes in.

Done.

[owen-d]

Thanks!

[hterik]

Hi
Being new to this, may i ask.

1. Why is request_timeout set to 0, when default value is 30.
   It's easier to understand examples if they only contain the absolute minimum required configuration. If this deviation from the default is important, an explanation why would be good, and maybe in that case the default should be reconsidered.

2. Why must the filesystem config be present?
   It appears counter-inuitive that one has to add filesystem config when wanting to use azure. Is this directory used for other temporary storage or is it a leftover from other config?

[thorker]

I stumpled at the same points.
Can someone please explain these configurations?