Grammar fix: Group's sidebar -> Groups sidebar

resources/langs/nheko_ca.ts

resources/langs/nheko_cs.ts

resources/langs/nheko_de.ts

resources/langs/nheko_el.ts

resources/langs/nheko_en.ts

resources/langs/nheko_eo.ts

resources/langs/nheko_es.ts

resources/langs/nheko_et.ts

resources/langs/nheko_fi.ts

resources/langs/nheko_fr.ts

resources/langs/nheko_hu.ts

resources/langs/nheko_id.ts

resources/langs/nheko_it.ts

resources/langs/nheko_ja.ts

resources/langs/nheko_ml.ts

resources/langs/nheko_nl.ts

resources/langs/nheko_pl.ts

resources/langs/nheko_pt_BR.ts

resources/langs/nheko_pt_PT.ts

resources/langs/nheko_ro.ts