Updating outdated dependencies

[abdulwahabone]

There seems to be a lot of outdated dependencies that requires updating. This will solve the isssue with the gatsby-react-router-scroll too.

What should be strategy for these updates?

• Update only Gatsby and React related dependencies and fix scroll issue
• Or Update all the dependencies at once.

Either way, it would require intensive testing throughout the docs. I would suggest to go with second option.