revert building docs with redirect (#17016)

.readthedocs.yml

@@ -19,18 +19,38 @@
 # Required
 version: 2
 
+submodules:
+  include: all
+  recursive: true
+
 # Build documentation in the docs/ directory with Sphinx
 # reference: https://docs.readthedocs.io/en/stable/config-file/v2.html#sphinx
 sphinx:
+  configuration: docs/source-pytorch/conf.py
   fail_on_warning: true
 
+# Build documentation with MkDocs
+#mkdocs:
+#  configuration: mkdocs.yml
+
+# Optionally build your docs in additional formats such as PDF and ePub
+formats:
+  - htmlzip
+  #- pdf
+
 build:
   os: ubuntu-20.04
   tools:
     python: "3.9"
-  commands:
-    - pip install "sphinx>=4.0, <5.0"
-    - pwd ; ls -lh ; ls -lh ./docs/source-redirect
-    - cd ./docs/source-redirect ; make html --jobs 2
-    - ls -lh ./docs ; ls -lh ./docs/build
-    - mkdir _readthedocs ; mv docs/build/html _readthedocs/html
+  apt_packages:
+    - texlive-latex-extra
+    - dvipng
+    - texlive-pictures
+
+# Optionally set the version of Python and requirements required to build your docs
+python:
+  install:
+    - requirements: requirements/pytorch/docs.txt
+    #- requirements: requirements.txt
+    - method: pip
+      path: .