Fix instructions on how to contribute to Instructor Notes

[maneesha]

What is the problem?

In the FAQ, it says To contribute to the Instructor Notes, click the “Improve this page” menu option in the upper right corner of the Instructor Notes page.
The Instructor Notes pages for the various Genomics lessons don't have that menu option. These pages also don't have the "Edit this page" link that the individual episodes do.

Location of problem (optional)

https://datacarpentry.org/genomics-workshop/faq#what-are-common-problems-that-arise-during-this-workshop