test: add basic temporal presence check

Author: legendecas

test/parallel/test-temporal.js

@@ -0,0 +1,14 @@
+// Flags: --harmony-temporal
+
+'use strict';
+const common = require('../common');
+const assert = require('assert');
+
+if (!process.config.variables.v8_enable_temporal_support) {
+  common.skip('Temporal is not enabled');
+}
+
+// Use globalThis.Temporal to workaround linter complaints.
+assert.strictEqual(typeof globalThis.Temporal, 'object');
+const instant = globalThis.Temporal.Instant.from('1969-07-20T20:17Z');
+assert.strictEqual(instant.toString(), '1969-07-20T20:17:00Z');