Docs: Add html redirects

- Since some .rst folders were renamed and reaaranged, this broke
  some existing links i.e. quickstart.html does not exist anymore since
  it was renamed to gettingstarted.html
- This patch establishes redirects so that the old changed html
  links still exists and redirect to the new links. For this a new
  dependency of sphinx_reredirects is added.

Task-number: PYSIDE-2837
Change-Id: I7af4a1ffef174b06fd8cb439ad1ccf52754c744d
Reviewed-by: Friedemann Kleint <[email protected]>

Author: ShyamQt

requirements-doc.txt

@@ -3,6 +3,7 @@ sphinx-design==0.6.0
 sphinx-copybutton==0.5.2
 sphinx-tags==0.4
 sphinx-toolbox==3.7.0
+sphinx-reredirects==0.1.5
 myst-parser==3.0.1
 # FIXME: Using fork in order to enable the 'collapse_navbar=True'
 # option for the sphinx-theme. Upstream proposal:

sources/pyside6/doc/conf.py.in

@@ -31,7 +31,7 @@ extensions = ['sphinx.ext.autodoc', 'sphinx.ext.doctest', 'sphinx.ext.ifconfig',
     'sphinx.ext.graphviz', 'inheritance_diagram', 'pysideinclude',
     'sphinx.ext.viewcode',
     'sphinx_design', 'sphinx_copybutton', 'myst_parser', 'sphinx_tags',
-    'sphinx_toolbox.decorators']
+    'sphinx_toolbox.decorators', 'sphinx_reredirects']
 
 myst_enable_extensions = [
     "amsmath",
@@ -242,3 +242,14 @@ tags_create_badges = True
 tags_badge_colors = {
     "Android": "info",
 }
+
+# link redirection in sphinx
+redirects = {
+    "gettingstarted/porting_from2.html": "../faq/porting_from2.html",
+    "gettingstarted/package_details.html": "../package_details.html",
+    "gettingstarted/index.html": "../building_from_source/index.html",
+    "gettingstarted/linux.html": "../building_from_source/linux.html",
+    "gettingstarted/windows.html": "../building_from_source/windows.html",
+    "gettingstarted/macOS.html": "../building_from_source/macOS.html",
+    "quickstart.html": "gettingstarted.html"
+}