network command modules cleanup (#45242)

* Standardize _command modules

* Centralize command transformation process

* Fix check mode error test

test/units/modules/network/ios/fixtures/configure_revert_now

@@ -1,2 +0,0 @@
-%No Rollback Confirmed Change pending
-

test/units/modules/network/ios/fixtures/configure_terminal

@@ -0,0 +1,2 @@
+
+

test/units/modules/network/ios/test_ios_command.py

@@ -107,19 +107,20 @@ class TestIosCommandModule(TestIosModule):
         set_module_args(dict(commands=commands, wait_for=wait_for, match='all'))
         self.execute_module(failed=True)
 
-    def test_ios_command_configure_error(self):
+    def test_ios_command_configure_check_warning(self):
         commands = ['configure terminal']
         set_module_args({
             'commands': commands,
             '_ansible_check_mode': True,
         })
-        result = self.execute_module(failed=True)
+        result = self.execute_module()
         self.assertEqual(
-            result['msg'],
-            'ios_command does not support running config mode commands.  Please use ios_config instead'
+            result['warnings'],
+            ['Only show commands are supported when using check mode, not executing configure terminal'],
         )
 
-    def test_ios_command_configure_not_error(self):
-        commands = ['configure revert now']
+    def test_ios_command_configure_not_warning(self):
+        commands = ['configure terminal']
         set_module_args(dict(commands=commands))
-        self.execute_module()
+        result = self.execute_module()
+        self.assertEqual(result['warnings'], [])