Skip Gemini test due to @google/genai getReader issue

The test was previously skipped but got reverted. Re-skipping to fix CI.

Co-authored-by: dallin <[email protected]>

Author: continue[bot]

core/llm/llm.test.ts

@@ -235,7 +235,7 @@ describe("LLM", () => {
       model: "gemini-2.0-flash-exp",
       apiKey: process.env.GEMINI_API_KEY,
     }),
-    { skip: false },
+    { skip: true }, // Skipped - @google/genai getReader issue
   );
   testLLM(
     new Mistral({