Add tests.

test/libyul/objectCompiler/namedObjectCode.yul

@@ -0,0 +1,13 @@
+object "a" {
+  code { sstore(0, 1) }
+}
+// ----
+// Assembly:
+//     /* "source":32:33   */
+//   0x01
+//     /* "source":29:30   */
+//   0x00
+//     /* "source":22:34   */
+//   sstore
+// Bytecode: 6001600055
+// Opcodes: PUSH1 0x1 PUSH1 0x0 SSTORE