remove callout: Object-oriented programming and Python classes

[ilessing]

While the content of this callout might be helpful to those interested in learning python in the context of learning web scraping it is likely to distract and overburden learners. In the interest of reducing this lesson length and streamlining it a bit....

Let's remove this content from the lesson.

Please comment if you think it is Okay to remove or if it should be kept.

file: https://github.com/UCSBCarpentry/CustomLibraryWebscraping/blob/gh-pages/_episodes/04-scrapy.md