Fix deprecation warnings emitted from hugo 0.158.0

[deining]

When running the site with latest released hugo version 0.158.0, deprecation warnings are printed out:

INFO  deprecated: project config key languages.en.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.en.label instead.
INFO  deprecated: project config key languages.no.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.no.label instead.
INFO  deprecated: project config key languages.fa.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.fa.label instead.
INFO  deprecated: project config key languages.fa.languageDirection was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.fa.direction instead.
INFO  deprecated: project config key languages.no.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.no.label instead.
INFO  deprecated: project config key languages.fa.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.fa.label instead.
INFO  deprecated: project config key languages.fa.languageDirection was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.fa.direction instead.
INFO  deprecated: project config key languages.en.languageName was deprecated in Hugo v0.158.0 and will be removed in a future release. Use languages.en.label instead.

See: https://discourse.gohugo.io/t/deprecations-in-v0-158-0/56869

This PR fixes these warnings.

[deining]

I just rebased this PR and resolved a merge conflict.
I would like to see this PR reviewed and merged soon otherwise this issue might by escalated to an error in a future hugo version.

[chalin]

Thanks! LGTM with Hugo version set to 0.158.0 (I'll make the edit).