Re-evaluate where link to flags in data submission FAQ should be pointing

[eaitoro]

Here is where this is currently referenced:

cchdo-learning-and-guides/docs/submitting_data/faq.md

Line 5 in 20edd06

The CCHDO uses WOCE quality flags that can be found in our [detailed submission guidelines](../submitting_data/detailed_guide.md#data-quality-evaluation-and-data-quality-flags).

[DocOtak]

Options are:

1. Continue to point to internal list of flags
2. Point at the exchange format spec (has been de facto canonical location)
3. Point at NVS when we get the flag defs in
4. Do 3. above but wait till they exist before doing anything