e2e testing: Assistant token count flake fix (#9228)

Assistant token count is flaking when the chat window needs scrolled to see all chat entries.  SInce this testing token count, if the count matches that implicitely means teh message count will be good as well.

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Author: jonvanausdeln

test/e2e/tests/positron-assistant/positron-assistant.test.ts

@@ -226,7 +226,6 @@ test.describe('Positron Assistant Chat Tokens', { tag: [tags.WIN, tags.ASSISTANT
 		await app.workbench.assistant.enterChatMessage(message2);
 
 		await app.workbench.assistant.waitForReadyToSend();
-		await app.workbench.assistant.verifyNumberOfVisibleResponses(2, true);
 
 		const totalTokens = await app.workbench.assistant.getTotalTokenUsage();
 		expect(totalTokens).toBeDefined();