Issue description

Support for Salesforce Sandbox with the ira Cloud for CRM (Official) Add-On.
Currently, the Salesforce Sandbox is not supported by the CRM app, with Jira.

Steps to replicate

• Create a Salesforce Sandbox
• Install the marketplace app Jira Cloud for CRM (Official) in Jira.
• Navigate to Project Settings -> CRM Integration and select Salesforce and click Continue
• Choose Use Custom Domain and key in the domain of the sandbox environment created.
• Proceed with allowing the permissions asked for.

Expected Results:

Integration succeeds

Actual results:

An authorization error appears.