feat: add Support for Postgres 15 (#114)

Author: joe1981al

README.md

@@ -6,7 +6,7 @@ GroupSync is a self-deployed example app that provides support for managing [Clo
 ## Supported Databases
 Currently only the following databases are supported:
 - **MySQL 8.0**
-- **PostgreSQL 14, 13, 12, 11, 10, 9.6**
+- **PostgreSQL 15, 14, 13, 12, 11, 10, 9.6**
 
 ## Overview
 The GroupSync example app at an overview is made of Cloud Scheduler Job(s) and Cloud Run instance(s).

iam_groups_authn/utils.py

@@ -43,6 +43,7 @@ class DatabaseVersion(Enum):
     All supported database versions for service."""
 
     MYSQL_8_0 = "MYSQL_8_0"
+    POSTGRES_15 = "POSTGRES_15"
     POSTGRES_14 = "POSTGRES_14"
     POSTGRES_13 = "POSTGRES_13"
     POSTGRES_12 = "POSTGRES_12"