Removed old sections from tox.ini

Author: domdfcoding

tox.ini

@@ -150,25 +150,3 @@ package = seed_intersphinx_mapping
 [pytest]
 addopts = --color yes --durations 25
 timeout = 300
-
-[gh-actions]
-python =
-    3.6: py36, build, mypy
-    3.7: py37, build
-    3.8: py38, build
-    3.9-dev: py39-dev, build
-
-[travis]
-python =
-    3.6: py36, build, mypy
-    3.7: py37, build
-    3.8: py38, build
-    3.9-dev: py39-dev, build
-
-[testenv:yapf]
-basepython = python3.7
-changedir = {toxinidir}
-skip_install = True
-ignore_errors = True
-deps = yapf
-commands = yapf -i --recursive seed_intersphinx_mapping tests