[style] apply google python style guide (#4501)

This commit applies and enforces Google's python style for tests.

tests/scripts/thread-cert/test_common.py

@@ -51,8 +51,9 @@ def any_ipv6_address():
 
 
 class TestMessageInfo(unittest.TestCase):
+
     def test_should_return_source_ipv6_value_when_source_ipv6_property_is_called(
-            self):
+        self):
         # GIVEN
         source_ipv6 = any_ipv6_address()
 
@@ -63,12 +64,11 @@ class TestMessageInfo(unittest.TestCase):
         actual_source_ipv6 = message_info.source_ipv6
 
         # THEN
-        self.assertEqual(
-            ipaddress.ip_address(bytes(source_ipv6)), actual_source_ipv6
-        )
+        self.assertEqual(ipaddress.ip_address(bytes(source_ipv6)),
+                         actual_source_ipv6)
 
     def test_should_return_destination_ipv6_value_when_destination_ipv6_property_is_called(
-            self):
+        self):
         # GIVEN
         destination_ipv6 = any_ipv6_address()
 
@@ -85,7 +85,7 @@ class TestMessageInfo(unittest.TestCase):
         )
 
     def test_should_return_source_eui64_value_when_source_eui64_property_is_called(
-            self):
+        self):
         # GIVEN
         source_mac_address = any_eui64()
 
@@ -99,7 +99,7 @@ class TestMessageInfo(unittest.TestCase):
         self.assertEqual(source_mac_address, actual_source_mac_address)
 
     def test_should_return_destination_eui64_value_when_destination_eui64_property_is_called(
-            self):
+        self):
         # GIVEN
         destination_mac_address = any_eui64()
 
@@ -110,14 +110,14 @@ class TestMessageInfo(unittest.TestCase):
         actual_destination_mac_address = message_info.destination_mac_address
 
         # THEN
-        self.assertEqual(
-            destination_mac_address, actual_destination_mac_address
-        )
+        self.assertEqual(destination_mac_address,
+                         actual_destination_mac_address)
 
 
 class TestMacAddress(unittest.TestCase):
+
     def test_should_create_MacAddress_from_eui64_when_from_eui64_classmethod_is_called(
-            self):
+        self):
         # GIVEN
         eui64 = any_eui64()
 
@@ -129,7 +129,7 @@ class TestMacAddress(unittest.TestCase):
         self.assertEqual(eui64, mac_address.mac_address)
 
     def test_should_create_MacAddress_from_rloc16_int_when_from_rloc16_classmethod_is_called(
-            self):
+        self):
         # GIVEN
         rloc16 = any_rloc16_int()
 
@@ -141,7 +141,7 @@ class TestMacAddress(unittest.TestCase):
         self.assertEqual(struct.pack(">H", rloc16), mac_address.mac_address)
 
     def test_should_create_MacAddress_from_rloc16_bytearray_when_from_rloc16_classmethod_is_called(
-            self):
+        self):
         # GIVEN
         rloc16 = any_rloc16_bytearray()
 
@@ -153,7 +153,7 @@ class TestMacAddress(unittest.TestCase):
         self.assertEqual(rloc16, mac_address.mac_address)
 
     def test_should_convert_short_MacAddress_to_iid_when_convert_method_is_called(
-            self):
+        self):
         # GIVEN
         rloc16 = any_rloc16_bytearray()
 
@@ -164,11 +164,10 @@ class TestMacAddress(unittest.TestCase):
 
         # THEN
         self.assertEqual(
-            bytearray([0x00, 0x00, 0x00, 0xff, 0xfe, 0x00]) + rloc16, iid
-        )
+            bytearray([0x00, 0x00, 0x00, 0xff, 0xfe, 0x00]) + rloc16, iid)
 
     def test_should_convert_eui64_MacAddress_to_iid_when_convert_method_is_called(
-            self):
+        self):
         # GIVEN
         eui64 = any_eui64()