Scheduled biweekly dependency update for week 33 (#807)

* Update flake8-isort from 3.0.0 to 4.0.0
* Update isort from 4.3.21 to 5.4.2
* Update sphinx from 3.1.1 to 3.2.1
* Update sphinx_rtd_theme from 0.4.3 to 0.5.0
* Update twine from 3.1.1 to 3.2.0
* Update factory-boy from 2.12.0 to 3.0.1
* Update faker from 4.1.0 to 4.1.1
* Update pytest from 5.4.3 to 6.0.1
* Update pytest-cov from 2.10.0 to 2.10.1

Co-authored-by: Oliver Sauder <sliverc@users.noreply.github.com>

Author: pyup-bot

requirements/requirements-codestyle.txt

@@ -1,3 +1,3 @@
 flake8==3.8.3
-flake8-isort==3.0.0
-isort==4.3.21
+flake8-isort==4.0.0
+isort==5.4.2

requirements/requirements-documentation.txt

@@ -1,3 +1,3 @@
 recommonmark==0.6.0
-Sphinx==3.1.1
-sphinx_rtd_theme==0.4.3
+Sphinx==3.2.1
+sphinx_rtd_theme==0.5.0

requirements/requirements-packaging.txt

@@ -1 +1 @@
-twine==3.1.1
+twine==3.2.0

requirements/requirements-testing.txt

@@ -1,7 +1,7 @@
 django-debug-toolbar==2.2
-factory-boy==2.12.0
-Faker==4.1.0
-pytest==5.4.3
-pytest-cov==2.10.0
+factory-boy==3.0.1
+Faker==4.1.1
+pytest==6.0.1
+pytest-cov==2.10.1
 pytest-django==3.9.0
 pytest-factoryboy==2.0.3