465 - Update Aurora default Parameter Group to 'default.aurora-postgr…

…esql11'. (#466)

### Feature or Bugfix
- Bugfix

### Detail
- Update Aurora default Parameter Group to
'default.aurora-postgresql11'. Fixes an issue where the Aurora nested
stack deploy in the data.all backend deploy would fail and/or block
indefinitely due to 'default.aurora-postgresql10' mismatch with version
11 of the Aurora database engine.

### Relates
- #465

By submitting this pull request, I confirm that my contribution is made
under the terms of the Apache 2.0 license.

Authored-by: rbernota <rbernota@yahooinc.com>

deploy/stacks/aurora.py

@@ -125,7 +125,7 @@ def __init__(
             deletion_protection=True,
             cluster_identifier=f'{resource_prefix}-{envname}-db',
             parameter_group=rds.ParameterGroup.from_parameter_group_name(
-                self, 'ParameterGroup', 'default.aurora-postgresql10'
+                self, 'ParameterGroup', 'default.aurora-postgresql11'
             ),
             enable_data_api=True,
             default_database_name=f'{envname}db',