fix(tests): resolve jest 30.4 + jsdom 26 compatibility issues

- Patch Object.defineProperties in jsDomWithFetchAPI.ts to make
  window.location configurable, enabling jest.spyOn in tests with
  jest-environment-jsdom 30 (which bundles jsdom 26)
- Update TableChart.test.tsx: jsdom 26 returns rgba(0,0,0,0) for
  elements with no background, replacing empty string expectations
- Apply prettier formatting fixes to logger.test.ts and
  RedirectWarning/utils.test.ts

Co-Authored-By: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

superset-frontend/spec/helpers/jsDomWithFetchAPI.ts

@@ -19,6 +19,38 @@
 
 import JSDOMEnvironment from 'jest-environment-jsdom';
 
+// jest-environment-jsdom 30 bundles jsdom 26, which marks window.location as
+// [LegacyUnforgeable] (configurable: false). jest 30's spyOn now strictly
+// checks the configurable flag and throws when it's false, breaking every test
+// that uses jest.spyOn(window, 'location', 'get').
+//
+// We intercept Object.defineProperties at module-load time (before any JSDOM
+// instance is created). The interceptor makes window.location configurable
+// every time jsdom creates a new Window, restoring the ability to spy on it.
+// This file is only required by Jest in the test environment so the
+// monkey-patch is safe.
+const _originalDefineProperties = Object.defineProperties.bind(Object);
+(Object as any).defineProperties = function (
+  obj: object,
+  props: PropertyDescriptorMap,
+) {
+  if (
+    props !== null &&
+    typeof props === 'object' &&
+    Object.prototype.hasOwnProperty.call(props, 'location') &&
+    (props as any).location?.configurable === false
+  ) {
+    // Allow jest.spyOn(window, 'location', 'get') to work in tests by making
+    // the property configurable. This deviates from the browser spec's
+    // [LegacyUnforgeable] requirement but is acceptable in a test environment.
+    props = {
+      ...props,
+      location: { ...(props as any).location, configurable: true },
+    };
+  }
+  return _originalDefineProperties(obj, props);
+};
+
 // https://github.com/facebook/jest/blob/v29.4.3/website/versioned_docs/version-29.4/Configuration.md#testenvironment-string
 export default class FixJSDOMEnvironment extends JSDOMEnvironment {
   constructor(...args: ConstructorParameters<typeof JSDOMEnvironment>) {