Updates to pin charm-tools to 2.8.3

* Update requirements.txt to pin charm-tools to 2.8.3
* Update tox.ini to change the build parameters.
* This upgrades from <2.7 which adds reproducible charms
* Bug was fixed that controlled the default output directory
  doesn't get 'builds' appended.  The tox change puts it
  back so that stable & master both build to the same
  directory.  This may be reviewed in the future.
* The cs:ubuntu charm used in the test has changed its behaviour
  regarding the workload status message.  The check in tests.yaml and in
  the zaza test have been relaxed so that the workload status message is
  not checked.

func-test-pr: https://github.com/openstack-charmers/zaza-openstack-tests/pull/521
Change-Id: I34f77b745e678e9e45e481a5179a9e23f31e51d4

requirements.txt

@@ -9,7 +9,7 @@
 setuptools<50.0.0  # https://github.com/pypa/setuptools/commit/04e3df22df840c6bb244e9b27bc56750c44b7c85
 
 # Build requirements
-charm-tools>=2.4.4,<2.8
+charm-tools==2.8.3
 
 # Workaround until https://github.com/juju/charm-tools/pull/589 gets
 # published

src/tests/tests.yaml

@@ -22,3 +22,6 @@ target_deploy_status:
   keystone-kerberos:
     workload-status: blocked
     workload-status-message:  "Kerberos configuration incomplete"
+  ubuntu-test-host:
+    workload-status: active
+    workload-status-message: ''

tox.ini

@@ -28,7 +28,7 @@ deps =
 [testenv:build]
 basepython = python3
 commands =
-    charm-build --log-level DEBUG -o {toxinidir}/build src {posargs}
+    charm-build --log-level DEBUG -o {toxinidir}/build/builds src {posargs}
 
 [testenv:py3]
 basepython = python3