chore: Translate transifex_input.json in pt_PT

88% of minimum 50% translated source file: 'transifex_input.json'
on 'pt_PT'.

Sync of partially translated files: 
untranslated content is included with an empty translation 
or source language content depending on file format

translations/frontend-app-authn/src/i18n/messages/pt_PT.json

@@ -24,7 +24,6 @@
   "institution.login.button": "Credenciais da instituição/campus",
   "login.other.options.heading": "Ou faça login com:",
   "enterprise.login.btn.text": "Credenciais da empresa ou escola",
-  "tab.back.btn.text": "Voltar",
   "forgot.password.confirmation.message": "We sent an email to {email} with instructions to reset your password. If you do not receive a password reset message after 1 minute, verify that you entered the correct email address, or check your spam folder. If you need further assistance, {supportLink}.",
   "forgot.password.page.title": "Esqueceu a Senha | {siteName}",
   "forgot.password.page.heading": "Redefinir palavra-passe",
@@ -155,9 +154,6 @@
   "terms.of.service": "Termos do Serviço",
   "registration.username.suggestion.label": "Sugerido:",
   "did.you.mean.alert.text": "Quis dizer",
-  "simplified.registration.exp.button": "Complete account creation",
-  "simplify.registration.username.guideline.content": "To finalize your registration, please confirm your country of residence and create a public username that will identify you in your course communication forums. The username cannot be changed.",
-  "simplify.registration.form.submission.error": "Please check your responses for this and the previous step and try again.",
   "sign.in": "Iniciar sessão",
   "reset.password.page.title": "Redefinir Palavra-passe | {siteName}",
   "reset.password": "Redefinir palavra-passe",