Fix the following typing problem in the tests:

rrweb:test:     test/utils.ts:181:43 - error TS2345: Argument of type 'elementNode & { rootId?: number | undefined; isShadowHost?: boolean | undefined; isShadow?: boolean | undefined; } & { id: number; }' is not assignable to parameter of type '{ attributes: { src?: string | undefined; }; }'.
rrweb:test:       Types of property 'attributes' are incompatible.
rrweb:test:         Type 'attributes' has no properties in common with type '{ src?: string | undefined; }'.
rrweb:test:
rrweb:test:     181               stripBlobURLsFromAttributes(add.node);

packages/rrweb/test/utils.ts

@@ -242,18 +242,18 @@ export function stringifySnapshots(snapshots: eventWithTime[]): string {
 
 function stripBlobURLsFromAttributes(node: {
   attributes: {
-    src?: string;
+    [key: string]: any;
   };
 }) {
-  if (
-    'src' in node.attributes &&
-    node.attributes.src &&
-    typeof node.attributes.src === 'string' &&
-    node.attributes.src.startsWith('blob:')
-  ) {
-    node.attributes.src = node.attributes.src
-      .replace(/[\w-]+$/, '...')
-      .replace(/:[0-9]+\//, ':xxxx/');
+  for (const attr in node.attributes) {
+    if (
+      typeof node.attributes[attr] === 'string' &&
+      node.attributes[attr].startsWith('blob:')
+    ) {
+      node.attributes[attr] = node.attributes[attr]
+        .replace(/[\w-]+$/, '...')
+        .replace(/:[0-9]+\//, ':xxxx/');
+    }
   }
 }