Add a taxonomy of variations in the environment variables

Add taxonomy of environment variable variations causing unreproducible builds.

Although, I'm uncertain if this is the ideal location for the taxonomy, I wanted to define each category and highlight notable instances within them. Additionally, I can include workarounds for some of the variations and/or provide links to relevant documentation explaining the workarounds.

Lastly, on my local instance, the image does not display on the webpage, however, I fail to identify the issue, whether it is with the image path or something else in the HTML itself.