state store query API: validate changes in the syntax of query JSON

[dmitsh]

Per work items below, the syntax of the state query JSON has been slightly changed, to make it more intuitive:
dapr/components-contrib#1490
dapr/components-contrib#1491
dapr/components-contrib#1500
dapr/docs#2195

Please validate this change in the SDK, and fix if necessary.

[mukundansundar]

related to #653

[mukundansundar]

/assign