Update API key policy

Author: thivindu

gateway/policies/api-key-auth/v1.0.0/apikey.go

@@ -66,10 +66,8 @@ var ins = &APIKeyPolicy{
 	},
 }
 
-// NewPolicy creates a new APIKeyPolicy instance
-func NewPolicy(
+func GetPolicy(
 	metadata policy.PolicyMetadata,
-	initParams map[string]interface{},
 	params map[string]interface{},
 ) (policy.Policy, error) {
 	return ins, nil