Add example from JSON Data Format docs to v2 tests

[RJKeevil]

Description

Demonstrates the issue raised in #265

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[RJKeevil]

@matthewmcneely Updated this PR now v2 is merged with v1. I think its very important to get this fixed as 1) the DQL docs are incompatatible with RunDQL, and 2) it's the single reason that I cannot use the new structure without rewriting hundreds of mutations.

[matthewmcneely]

it's the single reason that I cannot use the new structure without rewriting hundreds of mutations

@RJKeevil You should have a closer look at the final APIs for v25. The namespace concept was scaled back. You can create namespaces via gRPC, but you cannot name them (they just allocate the next ns ID and return an integer)... and you must assign users in those namespaces and login the old way for operations to take place in their respective namespaces.

In this light, you might as well keep your old transaction/setJSON code.