To cite the entire website use this snippet:

Symbiota Support Hub (2021). Symbiota Documentation. https://biokic.github.io/symbiota-docs/

To cite one particular page, you can use this template, or navigate to the bottom of the desired page and copy it from there:

[Content authors, editors and translators full names]. [Page Title]. In: Symbiota Support Hub (2021). Symbiota Documentation. [Permalink]. Created on [DD month YYYY], last edited on [DD month YYYY].