Bump VERSION for v0.5.6 development
Bump VERSION for v0.5.6 development

open-policy-agent/opa,tsandall/opa,tsandall/opa,Eva-xiaohui-luo/opa,Eva-xiaohui-luo/opa,open-policy-agent/opa,tsandall/opa,open-policy-agent/opa,tsandall/opa,tsandall/opa,Eva-xiaohui-luo/opa,open-policy-agent/opa,tsandall/opa,open-policy-agent/opa,open-policy-agent/opa