docs: update pagination usage in README.md (#855)

* chore: update README.md

* chore: fix page_size snakecase

---------

Co-authored-by: Shubham <[email protected]>

Author: manisha1997

README.md

@@ -193,6 +193,8 @@ The library automatically handles paging for you. Collections, such as `calls` a
 
 `list` eagerly fetches all records and returns them as a list, whereas `stream` returns an iterator and lazily retrieves pages of records as you iterate over the collection. You can also page manually using the `page` method.
 
+`page_size` as a parameter is used to tell how many records should we get in every page and `limit` parameter is used to limit the max number of records we want to fetch.
+
 #### Use the `list` method
 
 ```python
@@ -206,6 +208,21 @@ for sms in client.messages.list():
   print(sms.to)
 ```
 
+```python
+client.messages.list(limit=20, page_size=20)
+```
+This will make 1 call that will fetch 20 records from backend service.
+
+```python
+client.messages.list(limit=20, page_size=10)
+```
+This will make 2 calls that will fetch 10 records each from backend service.
+
+```python
+client.messages.list(limit=20, page_size=100)
+```
+This  will make 1 call which will fetch 100 records but user will get only 20 records.
+
 ### Asynchronous API Requests
 
 By default, the Twilio Client will make synchronous requests to the Twilio API. To allow for asynchronous, non-blocking requests, we've included an optional asynchronous HTTP client. When used with the Client and the accompanying `*_async` methods, requests made to the Twilio API will be performed asynchronously.