[xena] Ensure get_requests_for_local_unit doesn't fail on incomplete relation

This is a rebuild/make sync for charms to pickup the fix in charmhelpers to fix
any inadvertant accesses of ['ca'] in the relation data before it is available
from vault in the certificates relation.  Fix in charmhelpers is in [1].

[1] https://github.com/juju/charm-helpers/pull/828
Closes-Bug: #2028683

Change-Id: I4c108ff5c7b3c3b3b12aa4a840428a02e7190b9c

bindep.txt

@@ -0,0 +1,4 @@
+libffi-dev [platform:dpkg]
+libpq-dev [platform:dpkg]
+libxml2-dev [platform:dpkg]
+libxslt1-dev [platform:dpkg]

rebuild

@@ -2,4 +2,4 @@
 # when dependencies of the charm change,
 # but nothing in the charm needs to.
 # simply change the uuid to something new
-fa14a3e8-b3eb-11eb-9a1d-a73843f31142
+448d85f0-3ce0-11ee-8ebd-13350ae138fd

src/build.lock

@@ -225,6 +225,12 @@
       "package": "pyaml",
       "vcs": null,
       "version": "21.10.1"
+    },
+    {
+      "type": "python_module",
+      "package": "Cython",
+      "vcs": null,
+      "version": "0.29.36"
     }
   ]
 }

tox.ini

@@ -97,7 +97,8 @@ commands = stestr run --slowest {posargs}
 [testenv:pep8]
 basepython = python3
 deps = flake8==3.9.2
-       charm-tools==2.8.3
+       PyYAML==6.0.1
+       charm-tools==2.8.6
 commands = flake8 {posargs} src unit_tests
 
 [testenv:func-target]