Use PostgreSQL 10.7

Signed-off-by: Balasankar "Balu" C <balasankar@gitlab.com>

.gitlab/ci/rails.gitlab-ci.yml

@@ -6,7 +6,7 @@
 .use-pg-10: &use-pg-10
   services:
-    - postgres:10.0
+    - postgres:10.7
     - redis:alpine
 .use-mysql: &use-mysql

changelogs/unreleased/use-pg-10-7.yml

+---
+title: Use PostgreSQL 10.7 in tests
+merge_request: 28020
+author:
+type: other