[3.7] Doc: Bump sphinx. (GH-10676) (GH-10803)

(cherry picked from commit 2db96ae)

Co-authored-by: Julien Palard <[email protected]>

Author: miss-islington

.azure-pipelines/docs-steps.yml

@@ -12,7 +12,7 @@ steps:
   inputs:
     versionSpec: '>=3.6'
 
-- script: python -m pip install sphinx~=1.6.1 blurb python-docs-theme
+- script: python -m pip install sphinx==1.8.2 blurb python-docs-theme
   displayName: 'Install build dependencies'
 
 - ${{ if ne(parameters.latex, 'true') }}:

.travis.yml

@@ -43,7 +43,7 @@ matrix:
         - cd Doc
         # Sphinx is pinned so that new versions that introduce new warnings won't suddenly cause build failures.
         # (Updating the version is fine as long as no warnings are raised by doing so.)
-        - python -m pip install sphinx~=1.6.1 blurb
+        - python -m pip install sphinx==1.8.2 blurb
       script:
         - make check suspicious html SPHINXOPTS="-q -W -j4"
     - os: linux