Added translation of installation.mdx to Portuguese Issue #16824 (#16979)

* Added translation of installation.mdx to Portuguese, as well
as default templates of _toctree.yml and _config.py

* [ build_documentation.yml ] - Updated doc_builder to build
documentation in Portuguese.
[ pipeline_tutorial.mdx ] - Created translation for the pipeline_tutorial.mdx.

* [ build_pr_documentation.yml ] - Added pt language to pr_documentation builder.

[ pipeline_tutorial.mdx ] - Grammar changes.

* [ accelerate.mdx ] - Translated to Portuguese the acceleration tutorial.

* [ multilingual.mdx ] - Added portuguese translation for multilingual tutorial.

[ training.mdx ] - Added portuguese translation for training tutorial.

* [ preprocessing.mdx ] - WIP

* Update _toctree.yml

* Adding Pré-processamento to _toctree.yml

* Update accelerate.mdx

* Nits and eliminate preprocessing file while it is ready

Co-authored-by: Omar U. Espejel <espejelomar@gmail.com>

docs/source/pt/_toctree.yml

@@ -0,0 +1,16 @@
+- sections:
+  - local: installation
+    title: Instalação
+  title: Iniciar
+- sections:
+  - local: pipeline_tutorial
+    title: Pipelines para inferência
+  - local: training
+    title: Fine-tuning de um modelo pré-treinado
+  - local: accelerate
+    title: Treinamento distribuído com 🤗 Accelerate
+  title: Tutoriais
+- sections:
+  - local: multilingual
+    title: Modelos multilinguísticos para inferência
+  title: Guias práticos