Review runner documentation

[solidgoldpig]

No description provided.

[umaar]

Docs are looking great

Thoughts:

As a general note, almost all doc links are broken

Also lots of TODOs which can be addressed.

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https://github.com/ministryofjustice/form-builder/blob/master/documentation/running/runner/storage.md

I think it's config instead now?

There will be an option to enable persistent storage.

Would be good to clarify what this means, as in when/how?

Read more about dynamoDb

This doesn't link to anything, but I think we're using RDS/Postgres now?

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https://github.com/ministryofjustice/form-builder/blob/master/documentation/running/runner/pattern.md - needs updating, e.g. with an example of a pattern

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https://github.com/ministryofjustice/form-builder/blob/master/documentation/running/runner/block.md#optional-properties

_isa _id of another block that the block is based on and which it inherit properties from. Any properties defined in the block override those set in the referenced block.

The wording of this could be improved - not sure I follow it! Also an explanation of what isa stands for