Document using `copr` GSSAPI

[LecrisUT]

IMO this should be the default configuration over the API tokens.

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/fd8fcf953c4e468c903e01a5ba0d9e0e

:heavy_check_mark: pre-commit SUCCESS in 6m 06s :heavy_check_mark: hugo SUCCESS in 2m 00s

[softwarefactory-project-zuul[bot]]

Build failed (gate pipeline).

https://softwarefactory-project.io/zuul/t/packit-service/buildset/82686cb5dda442c392242b8959f53aae

:x: pre-commit FAILURE in 1m 15s

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/5a248550371e4476b600983ec7e70add

:heavy_check_mark: pre-commit SUCCESS in 1m 15s :heavy_check_mark: hugo SUCCESS in 1m 03s

[softwarefactory-project-zuul[bot]]

Build succeeded (gate pipeline). https://softwarefactory-project.io/zuul/t/packit-service/buildset/e9ca74c2f65349b08c1098d09749aeb2

:heavy_check_mark: pre-commit SUCCESS in 1m 19s