Fix the bug of pep8 and building api-guide

`sphinx-build` command is not found in test-env.

To fix pep8, also blacklist the new bandit warning B105, this will
be fixed in a followup.

Change-Id: Ic1b8c3a4bfd67fff082297b881df66ffb9ca2c50

tox.ini

@@ -50,7 +50,7 @@ commands =
   doc8 {posargs}
   flake8 {posargs}
   # Run security linter
-  bandit -r barbican -x tests -n5
+  bandit -r barbican -x tests -n5 -s B105
 
 [testenv:genconfig]
 basepython = python3
@@ -91,6 +91,7 @@ whitelist_externals = rm
 basepython = python3
 # This environment is called from CI scripts to test and publish
 # the API Guide to developer.openstack.org.
+deps = -r{toxinidir}/doc/requirements.txt
 commands =
   rm -rf api-guide/build
   sphinx-build -W -b html -d api-guide/build/doctrees api-guide/source api-guide/build/html
@@ -148,7 +149,7 @@ exclude = .git,.idea,.tox,bin,dist,debian,rpmbuild,tools,*.egg-info,*.eggs,contr
 [testenv:bandit]
 basepython = python3
 deps = -r{toxinidir}/test-requirements.txt
-commands = bandit -r barbican -x tests -n5
+commands = bandit -r barbican -x tests -n5 -s B105
 
 [testenv:bindep]
 basepython = python3