Payment Modal does not close when using plugin with test invironments.

[iCaspar]

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• Made sure you’re on the latest version ✅ 1.9.14
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Describe the bug When using the plugin with our staging and test versions of the app, the pricing modal does not close after completing a purchase transaction.

To Reproduce Steps to reproduce the behavior:

1. Point the app api URL to one of the test app URIs
2. Complete a test purchase in the plugin's pricing/checkout modal.
3. See the modal does not close after the transaction completes.

Expected behavior The modal should close correctly in conjunction any app environment.

Additional Context This issue is the only issue left from #558, which was trying to solve issues around the pricing modal that arose on-the-fly during the 2021 spring campaign.

Backlog Grooming (for WP Media dev team use only)

• [X] Reproduce the problem
• [X] Identify the root cause -- the test and development URIs are not set correctly in the pricing modal js.
• [X] Scope a solution -- add the correct URIs into the checkPluginMessage() method in pricing-modal.js
• [X] Estimate the effort: [XS]

[mostafa-hisham]

this PR will fix this issue but in a different way because we will define the URL in one place and send it to js we don't need to add multiple case for each environment URL

[mostafa-hisham]

Blocked by issue https://github.com/wp-media/imagify/issues/1580