Add link to platform overview in docs

[SmittieC]

Ticket

This is a documentation update

Environments Affected

None

[zandre-eng]

Just a tiny grammer comment. Looks good otherwise. I don't think there's anything more we need to add (I don't see any other relevant diagrams on HQ read-the-docs).

[zandre-eng]

Suggested change

	and the `Platform Overview <https://commcare-hq.readthedocs.io/overview/platform.html>`_ the CommCare HQ documentation.
	and the `Platform Overview <https://commcare-hq.readthedocs.io/overview/platform.html>`_ in the CommCare HQ documentation.

[SmittieC]

See this.

[mkangia]

nit: There is no one way to do this, though my preference would be to not club architecture and platform links together.
Architecture is probably the most relevant link followed by the data flow diagram I shared in the ticket

So I would say we make this look something like the following:

Architecture and Platform Overview
<same as before>
Other useful links:
- [Platform overview](https://commcare-hq.readthedocs.io/overview/platform.html)

Data Flow Overview
https://commcare-hq.readthedocs.io/overview/architecture.html#data-flow-for-forms-and-cases

[mkangia]

I think its fine if we skip the platform overview and add that to the architecture overview page itself.
Its quite scary and I don't think it is really useful for hosters unless someone is doing a deep understanding

[SmittieC]

How's this?

[mkangia]

Cool