Temporary fix for bitnami migration to secure images (#4626)

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A temp solution for #4625, but a long term solution would be migrating
to a supported PostgresSQL docker image w/o a paid subscription service.

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 - [ ] Ensure tests run with the legacy bitnami PostgreSQL image

Author: wes-otf

.github/workflows/hypha-ci.yml

@@ -38,7 +38,7 @@ jobs:
 
     services:
       postgres:
-        image: bitnami/postgresql:17
+        image: bitnamilegacy/postgresql:17
         env:
           POSTGRESQL_USERNAME: hypha
           POSTGRESQL_PASSWORD: hypha