Bump sphinx from 3.4.3 to 3.5.4

Bumps [sphinx](https://github.com/sphinx-doc/sphinx) from 3.4.3 to 3.5.4.
- [Release notes](https://github.com/sphinx-doc/sphinx/releases)
- [Changelog](https://github.com/sphinx-doc/sphinx/blob/4.x/CHANGES)
- [Commits](sphinx-doc/sphinx@v3.4.3...v3.5.4)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]

Diff for: docs-requirements.txt

@@ -12,7 +12,7 @@ certifi==2020.12.5
     # via requests
 chardet==4.0.0
     # via requests
-docutils==0.17.1
+docutils==0.16
     # via sphinx
 idna==2.10
     # via requests
@@ -34,7 +34,7 @@ requests==2.25.1
     # via sphinx
 snowballstemmer==2.1.0
     # via sphinx
-sphinx==3.4.3
+sphinx==3.5.4
     # via -r docs-requirements.in
 sphinxcontrib-applehelp==1.0.2
     # via sphinx

Diff for: test-requirements.txt

@@ -22,7 +22,7 @@ coverage==5.5
     # via pytest-cov
 cssselect==1.1.0
     # via -r test-requirements.in
-docutils==0.17.1
+docutils==0.16
     # via sphinx
 idna==2.10
     # via requests
@@ -60,7 +60,7 @@ requests==2.25.1
     # via sphinx
 snowballstemmer==2.1.0
     # via sphinx
-sphinx==3.4.3
+sphinx==3.5.4
     # via -r test-requirements.in
 sphinxcontrib-applehelp==1.0.2
     # via sphinx