Fix: remove Gemini and use OpenAI model for presubmit workflow

Author: N-Yashwitha

.github/workflows/presubmit.yml

@@ -1,15 +1,9 @@
 name: Presubmit.ai
 
-permissions:
-  contents: read
-  pull-requests: write
-  issues: write
-
 on:
   pull_request:
     types: [opened, synchronize, reopened]
 
-
 jobs:
   review:
     runs-on: ubuntu-latest
@@ -21,16 +15,10 @@ jobs:
             exit 1
           fi
 
-      - name: Check out PR code
-        uses: actions/checkout@v3
-        with:
-          ref: ${{ github.event.pull_request.head.sha }}
-
       - name: Run AI Reviewer
-  uses: presubmit/ai-reviewer@latest
-  env:
-    GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-    LLM_API_KEY: ${{ secrets.LLM_API_KEY }}
-    LLM_PROVIDER: "openai"
-    LLM_MODEL: "gpt-4-turbo"
-
+        uses: presubmit/ai-reviewer@latest
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+          LLM_API_KEY: ${{ secrets.LLM_API_KEY }}
+          LLM_PROVIDER: "openai"
+          LLM_MODEL: "gpt-4-turbo"