Add benefits of using packit to faq

[kapr200]

Adds the Documentation about aditional benefits of Packit compared to usage of external services directly.

Fixes #794

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/385b51b383dc46e08e4e7c4029776439

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

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/e2fc465803b54374bbc3412b05cbf5a3

:heavy_check_mark: pre-commit SUCCESS in 1m 21s

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/eec32424704640308bca2dc2b711b0df

:heavy_check_mark: pre-commit SUCCESS in 1m 22s

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/3bd4f090bf6d4c3baa11bff2aa692a63

:heavy_check_mark: pre-commit SUCCESS in 1m 18s

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/a2e914fb766447bbb9aa31d056d59d8e

:heavy_check_mark: pre-commit SUCCESS in 5m 41s

[softwarefactory-project-zuul[bot]]

Build succeeded. https://softwarefactory-project.io/zuul/t/packit-service/buildset/4fb0ce6a1d0e433cbe15311514df032b

:heavy_check_mark: pre-commit SUCCESS in 9m 31s

[softwarefactory-project-zuul[bot]]

Build succeeded (gate pipeline). https://softwarefactory-project.io/zuul/t/packit-service/buildset/6f1345bf95924c0ab0238db92d5d3c86

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