updates needed for error improvements PR

[jennifer-shehane]

TODO:

• Do not merge until Reporter error improvements cypress#3930 is merged for specific version

• close Update docs for error improvements #2374

• close Add docs for error improvements #2421 (previous docs PR that had these changes)

Docs for error improvements including:

• New ‘Errors’ section in ‘Debugging’, ‘Test Runner’, and ‘Writing your first test’
• New ‘File Opener Preference’ section in IDE Integration doc
• updated screenshots of errors

[jennifer-shehane]

@chrisbreiding I'm not sure if any changes have been made to the feature since we last wrote these that would affect the docs. Can you review?

[chrisbreiding]

Looks good outside of some minor nitpicks. Nothing has changed since this content was originally written, so I think it covers everything.