test(e2e): drop DomainWidgetAssetCount spec — coverage already in DomainDataProductsWidgets

DomainWidgetAssetCount.spec.ts requires persona+widget-assignment setup to
guarantee KnowledgePanel.Domains is visible on the home page before checking
counts. Without that setup the poll always returns null and the test fails.

DomainDataProductsWidgets.spec.ts already covers the exact same code paths
("Domain asset count should update when assets are added/removed") with the
correct setup. Remove the redundant spec and drop its impact-map entry.

The widget cache-invalidation fix (queryClient.invalidateQueries) and the
useMemo dep fix (assetsCounts) remain in the PR — they are exercised by
DomainDataProductsWidgets.spec.ts.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: anuj-kumary

.github/playwright/impact-map.json

@@ -296,7 +296,6 @@
       ],
       "projects": ["chromium", "Basic"],
       "specs": [
-        "playwright/e2e/Features/LandingPageWidgets/DomainWidgetAssetCount.spec.ts",
         "playwright/e2e/Features/LandingPageWidgets/DomainDataProductsWidgets.spec.ts"
       ]
     },