Fix environmental variables table display

[LesnyRumcajs]

Summary

Tables such as those on https://docs.forest.chainsafe.io/reference/env_variablesare scaling poorly on a wide screen 21:9

We can see that the table is shrunk and has to be scrolled horizontally, even though there's ample space on the sides to display it in full.

Completion Criteria

• Fix the display of the environmental variables table
• Assert that it works on various screen sizes (ask folks, change window size...)

Additional Links & Resources

Migrated from https://github.com/ChainSafe/forest-docs-v2/issues/96