Fixing un-versioned example (data/system)
Fixing un-versioned example (data/system)

- Added HTTP request snippet
- JSON payload needs to be an array. sprintf requires an array
  as second operand.
  See server_test.go tests for data/system for reference

Signed-off-by: repenno <8d028a2cce5a6653b616986f5e1fffa95594535f@gmail.com>

open-policy-agent/opa,open-policy-agent/opa,open-policy-agent/opa,tsandall/opa,tsandall/opa,tsandall/opa,open-policy-agent/opa,tsandall/opa,tsandall/opa,tsandall/opa,open-policy-agent/opa,open-policy-agent/opa