test: remove ERP tests (#451)

Slack conversation here:
https://comicrelief.slack.com/archives/CFMTAQ8UT/p1775727549819129

Author: KrupaPammi

playwright-staging/package.json

@@ -16,7 +16,6 @@
     "uuid": "8.3.2"
   },
   "scripts": {
-    "test:sanity": "FORCE_COLOR=1 playwright test --grep '@sanity'",
-    "test:regression": "FORCE_COLOR=1 playwright test --grep '@regression'"
+    "test:sanity": "FORCE_COLOR=1 playwright test --grep '@sanity'"
   }
 }

playwright-staging/playwright.config.js

@@ -26,7 +26,7 @@ const config = {
     scriptTimeout: 60000, // this is needed for long running scripts
     serviceWorkers: 'block', // optional but reduces flakiness
   },
-  grep: [new RegExp('@regression'), new RegExp('@sanity'), new RegExp('@nightly-sanity')],
+  grep: [new RegExp('@sanity')],
 
   /* Configure projects for major browsers */
   projects: [