docs: add Xurrent IMR and Shiprail to third-party integrations (#17198)

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## DESCRIBE YOUR PR
Adding two more third party integrations to the docs.

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## EXTRA RESOURCES

- [Sentry Docs contributor guide](https://docs.sentry.io/contributing/)

Author: souredoutlook

docs/organization/integrations/third-party-integrations/index.mdx

@@ -28,3 +28,5 @@ To build and publish your own, see the [Integration Platform docs](/organization
 - [Aether](https://docs.runaether.dev/introduction) {/* aether */}
 - [Toolbar](https://docs.usetool.bar/integrations/sentry) {/* toolbar */}
 - [Vanta Gov](https://help.vanta.com/en/articles/11345687-vanta-sentry-integration) {/* vanta-gov */}
+- [Xurrent IMR](https://zenduty.com/docs/sentry-integration/) {/* xurrent-imr */}
+- [Shiprail](https://www.shiprail.ai/) {/* shiprail */}

redirects.js

@@ -724,6 +724,14 @@ const userDocsRedirects = [
     source: '/organization/integrations/vanta-gov/',
     destination: '/organization/integrations/third-party-integrations/',
   },
+  {
+    source: '/organization/integrations/xurrent-imr/',
+    destination: '/organization/integrations/third-party-integrations/',
+  },
+  {
+    source: '/organization/integrations/shiprail/',
+    destination: '/organization/integrations/third-party-integrations/',
+  },
   {
     source: '/development/sdk-dev/:path*',
     destination: 'https://develop.sentry.dev',