Support PostgreSQL en_US.UTF-8 collation

Problem Definition

Currently, Jira only supports POSIX.UTF-8 or C.UTF-8 or C or POSIX as the collation.

Suggested Solution

Have Jira support *.UTF-8 collation (e.g. en_US.UTF-8, ja_JP.UTF-8) for PostgreSQL

Why this is important

Amazon AWS RDS has limited collation for PostgreSQL and en_US.UTF-8 is set as a default collation.

• Based on the discussion in Community, the collation is not easily updated - https://community.atlassian.com/t5/Jira-Software-questions/PostgreSQL-SSL-Configuration-Causes-Collation-Exception-on/qaq-p/649814
• Clients that are hosting Jira Data Center on AWS RDS with PostgreSQL would want to be on supported collation

Workaround

Move to the supported collation referring to https://confluence.atlassian.com/jirakb/how-to-fix-the-collation-of-a-postgres-jira-database-776657961.html