feature add exec method

src/test/kotlin/fr/postgresjson/ConnectionTest.kt

@@ -1,5 +1,6 @@
 package fr.postgresjson
 
+import com.github.jasync.sql.db.util.isCompleted
 import fr.postgresjson.connexion.Connection
 import fr.postgresjson.entity.IdEntity
 import org.junit.jupiter.api.Assertions.*
@@ -63,4 +64,12 @@ class ConnectionTest(): TestAbstract() {
         assertTrue(obj!!.id == 1)
         assertTrue(obj.name == "myName")
     }
+
+    @Test
+    fun callExec() {
+        val o = ObjTest("myName")
+        val future = connection.exec("select json_build_object('id', 1, 'name', ?::json->>'name')", listOf(o))
+        future.join()
+        assertTrue(future.isCompleted)
+    }
 }