Fix various typos in the templates (Ruby, C#) (#1803)

* Fix typos

* update petstore samples

samples/client/petstore/csharp/OpenAPIClientNetStandard/docs/UserApi.md

@@ -16,7 +16,7 @@ Method | HTTP request | Description
 
 <a name="createuser"></a>
 # **CreateUser**
-> void CreateUser (User user)
+> void CreateUser (User body)
 
 Create user
 
@@ -37,12 +37,12 @@ namespace Example
         public void main()
         {
             var apiInstance = new UserApi();
-            var user = new User(); // User | Created user object
+            var body = new User(); // User | Created user object
 
             try
             {
                 // Create user
-                apiInstance.CreateUser(user);
+                apiInstance.CreateUser(body);
             }
             catch (Exception e)
             {
@@ -57,7 +57,7 @@ namespace Example
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **user** | [**User**](User.md)| Created user object | 
+ **body** | [**User**](User.md)| Created user object | 
 
 ### Return type
 
@@ -76,7 +76,7 @@ No authorization required
 
 <a name="createuserswitharrayinput"></a>
 # **CreateUsersWithArrayInput**
-> void CreateUsersWithArrayInput (List<User> user)
+> void CreateUsersWithArrayInput (List<User> body)
 
 Creates list of users with given input array
 
@@ -95,12 +95,12 @@ namespace Example
         public void main()
         {
             var apiInstance = new UserApi();
-            var user = new List<User>(); // List<User> | List of user object
+            var body = new List<User>(); // List<User> | List of user object
 
             try
             {
                 // Creates list of users with given input array
-                apiInstance.CreateUsersWithArrayInput(user);
+                apiInstance.CreateUsersWithArrayInput(body);
             }
             catch (Exception e)
             {
@@ -115,7 +115,7 @@ namespace Example
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **user** | [**List&lt;User&gt;**](List.md)| List of user object | 
+ **body** | [**List&lt;User&gt;**](List.md)| List of user object | 
 
 ### Return type
 
@@ -134,7 +134,7 @@ No authorization required
 
 <a name="createuserswithlistinput"></a>
 # **CreateUsersWithListInput**
-> void CreateUsersWithListInput (List<User> user)
+> void CreateUsersWithListInput (List<User> body)
 
 Creates list of users with given input array
 
@@ -153,12 +153,12 @@ namespace Example
         public void main()
         {
             var apiInstance = new UserApi();
-            var user = new List<User>(); // List<User> | List of user object
+            var body = new List<User>(); // List<User> | List of user object
 
             try
             {
                 // Creates list of users with given input array
-                apiInstance.CreateUsersWithListInput(user);
+                apiInstance.CreateUsersWithListInput(body);
             }
             catch (Exception e)
             {
@@ -173,7 +173,7 @@ namespace Example
 
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
- **user** | [**List&lt;User&gt;**](List.md)| List of user object | 
+ **body** | [**List&lt;User&gt;**](List.md)| List of user object | 
 
 ### Return type
 
@@ -426,7 +426,7 @@ No authorization required
 
 <a name="updateuser"></a>
 # **UpdateUser**
-> void UpdateUser (string username, User user)
+> void UpdateUser (string username, User body)
 
 Updated user
 
@@ -448,12 +448,12 @@ namespace Example
         {
             var apiInstance = new UserApi();
             var username = username_example;  // string | name that need to be deleted
-            var user = new User(); // User | Updated user object
+            var body = new User(); // User | Updated user object
 
             try
             {
                 // Updated user
-                apiInstance.UpdateUser(username, user);
+                apiInstance.UpdateUser(username, body);
             }
             catch (Exception e)
             {
@@ -469,7 +469,7 @@ namespace Example
 Name | Type | Description  | Notes
 ------------- | ------------- | ------------- | -------------
  **username** | **string**| name that need to be deleted | 
- **user** | [**User**](User.md)| Updated user object | 
+ **body** | [**User**](User.md)| Updated user object | 
 
 ### Return type