[GCP] Forwarding Rule module (#24627)

* [GCP] Forwarding Rule module

* pep8 formatting for tests

* remove py26 check and updated_ key; docs and typo fixes

test/units/modules/cloud/google/test_gcp_forwarding_rule.py

@@ -0,0 +1,30 @@
+import unittest
+
+from ansible.modules.cloud.google.gcp_forwarding_rule import _build_global_forwarding_rule_dict
+
+
+class TestGCPFowardingRule(unittest.TestCase):
+    """Unit tests for gcp_fowarding_rule module."""
+    params_dict = {
+        'forwarding_rule_name': 'foo_fowarding_rule_name',
+        'address': 'foo_external_address',
+        'target': 'foo_targetproxy',
+        'region': 'global',
+        'port_range': 80,
+        'protocol': 'TCP',
+        'state': 'present',
+    }
+
+    def test__build_global_forwarding_rule_dict(self):
+
+        expected = {
+            'name': 'foo_fowarding_rule_name',
+            'IPAddress': 'https://www.googleapis.com/compute/v1/projects/my-project/global/addresses/foo_external_address',
+            'target': 'https://www.googleapis.com/compute/v1/projects/my-project/global/targetHttpProxies/foo_targetproxy',
+            'region': 'global',
+            'portRange': 80,
+            'IPProtocol': 'TCP',
+        }
+        actual = _build_global_forwarding_rule_dict(
+            self.params_dict, 'my-project')
+        self.assertEqual(expected, actual)