Cap jsonschema 3.2.0 as the minimal version

Previous versions of jsonschema (<3.2.0) doesn't support python 3.8 [1].
Python 3.8 is part of the victoria supported runtimes [2] so we now force
to use jsonschema version 3.2.0 to avoid issues, remove ambiguity and ensure
that everything works with python 3 in general.

[1] python-jsonschema/jsonschema#627
[2] https://governance.openstack.org/tc/reference/runtimes/victoria.html#python-runtimes-for-victoria

Change-Id: I511faa17b27eac827922957e4b36108da0dcd0c8

Author: 4383

lower-constraints.txt

@@ -46,7 +46,7 @@ Jinja2==2.10
 jmespath==0.9.3
 jsonpatch==1.21
 jsonpointer==2.0
-jsonschema==2.6.0
+jsonschema==3.2.0
 keystoneauth1==3.4.0
 keystonemiddleware==4.17.0
 kombu==4.1.0

requirements.txt

@@ -24,7 +24,7 @@ python-neutronclient>=6.7.0 # Apache-2.0
 python-glanceclient>=2.8.0 # Apache-2.0
 python-troveclient>=2.2.0 # Apache-2.0
 iso8601>=0.1.11 # MIT
-jsonschema>=2.6.0 # MIT
+jsonschema>=3.2.0 # MIT
 Jinja2>=2.10 # BSD License (3 clause)
 pexpect!=3.3,>=3.1 # ISC License
 oslo.config>=5.2.0 # Apache-2.0