Fix dbi ipv6 localhost

[Paamicky]

Description of the issue

When customers configure Database Insights with an IPv6 loopback endpoint ([::1]:5432), the isLocalhostEndpoint function does not recognize the bracketed IPv6 format as a local address. This causes the agent to attempt an SSL connection to localhost, which fails with pq: SSL is not enabled on the server when PostgreSQL does not have SSL configured.

Description of changes

Added [::1] to the isLocalhostEndpoint check in the DBI translator. This ensures IPv6 loopback addresses in the standard bracket notation are correctly identified as localhost.

Agent config

{
  "agent": {
    "region": "us-east-1"
  },
  "opentelemetry": {
    "collect": {
      "database_insights": {
        "postgresql": [
          {
            "endpoint": "[::1]:5432",
            "instance_name": "ipv6-test",
            "username": "cw_monitor",
            "password_file": "/opt/databaseinsights/.pgpass"
          }
        ]
      }
    }
  }
}

Tests

• Updated TestIsLocalhostEndpoint with [::1]:5432 test case
• Manually validated on EC2 instance: configured DBI with "endpoint": [::1]:5432, confirmed the agent connects to PostgreSQL over IPv6 without SSL errors and scrapes metrics successfully

License

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