Improve CT Examples

[elylucas]

from docs rally:

• "Very clear, but might it be good to have an example of passing in a spy to check if callbacks have fired correctly?"
• "It is super important for the user to understand the configuration files before you guide them to ‘customize cy.mount()’ or ‘redux’ in the 'react examples' sections. Cause the first thing I’m thinking is why am I editing stuff in this file and what does the file even do? So some pointer to the configuration files would be helpful for me"
• "Seems fine, but it would be good to know for future reference if there are any examples that we would like to add in the future -- we can ask the community to help out in a future Hacktoberfest"
• "This is well done. This is the example I used to run my component tests. The only problem is still, we don't have the definition of the component, we can infer, but not good to make assumptions!" - perhaps add a tab to show component