Kilo: release oslo.db 1.7.3

We need this to get alembic capped in oslo.db on stable/kilo
else we pull in alembic 0.8.4 which breaks nova's unit tests.

Changes since 1.7.2:

c5f468d Updated from global requirements
d0a169c Updated from global requirements
c30c28f Updated from global requirements
0beecc6 Updated from global requirements
f66d9c8 Updated from global requirements
40acac6 Add mock to test-requirements.txt

Change-Id: I3ace3d5278d3130e77e858d1368b43e1e40eb48f
Related-Bug: #1526675

deliverables/kilo/oslo.db.yaml

@@ -37,3 +37,9 @@ releases:
     projects:
       - repo: openstack/oslo.db
         hash: 88277a07d304a1f88fc08d44917852a46e2bd857
+  - version: 1.7.3
+    projects:
+      - repo: openstack/oslo.db
+        hash: c5f468d8fb237842aad54e5fdebd35a8be19df51
+    highlights: >
+        Dependency updates (caps synced from stable/kilo global-requirements).