Added support for openproject as exx app through proxy

[SagarGi]

Description

Related Issue or Workpackage

• Fixes <issue_link>

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Updated CHANGELOG.md file

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