Update code to Jinja 3.0 style

Xena cycle uses Jinja 3.0 so let update Kolla's code for it.

From Jinja2 documentation:

jinja2.contextfunction(f: F) → F
    Pass the context as the first argument to the decorated function.
    Deprecated since version 3.0: Will be removed in Jinja 3.1. Use pass_context() instead.

jinja2.contextfilter(f)
    Pass the context as the first argument to the decorated function.
    Deprecated since version 3.0: Will be removed in Jinja 3.1. Use pass_context() instead.

Also bumped version in requirements.txt to same as in openstack/requirements

Change-Id: I51fbb7b9ff7c29cb355437efa4576be9bc035699

kolla/template/filters.py

@@ -12,11 +12,11 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from jinja2 import contextfilter
+from jinja2 import pass_context
 from jinja2 import Undefined
 
 
-@contextfilter
+@pass_context
 def customizable(context, val_list, call_type):
     # NOTE(mgoddard): Don't try to customise undefined values. There are cases
     # where this might happen, for example using a generic template overrides

kolla/template/methods.py

@@ -15,7 +15,7 @@
 import os
 import yaml
 
-from jinja2 import contextfunction
+from jinja2 import pass_context
 
 
 def debian_package_install(packages, clean_package_cache=True):
@@ -71,7 +71,7 @@ def debian_package_install(packages, clean_package_cache=True):
     return ' && '.join(cmds)
 
 
-@contextfunction
+@pass_context
 def handle_repos(context, reponames, mode):
     """NOTE(hrw): we need to handle CentOS, Debian and Ubuntu with one macro.
 

requirements.txt

@@ -1,5 +1,5 @@
 pbr!=2.1.0,>=2.0.0 # Apache-2.0
 docker>=2.4.2 # Apache-2.0
-Jinja2>=2.8 # BSD License (3 clause)
+Jinja2>=3.0.1 # BSD License (3 clause)
 GitPython>=1.0.1 # BSD License (3 clause)
 oslo.config>=5.1.0 # Apache-2.0