[CI]: reduce HTTP calls inside entrypoints openai tests (#23646)

Signed-off-by: AzizCode92 <azizbenothman76@gmail.com>
Signed-off-by: Aziz <azizbenothman76@gmail.com>
Co-authored-by: Harry Mellor <19981378+hmellor@users.noreply.github.com>

tests/entrypoints/conftest.py

@@ -201,3 +201,32 @@ table: "table_1" | "table_2"
 condition: column "=" number
 number: "1" | "2"
 """)
+
+
+@pytest.fixture(scope="session")
+def zephyr_lora_files():
+    """Download zephyr LoRA files once per test session."""
+    from huggingface_hub import snapshot_download
+    return snapshot_download(repo_id="typeof/zephyr-7b-beta-lora")
+
+
+@pytest.fixture(scope="session")
+def zephyr_lora_added_tokens_files(zephyr_lora_files):
+    """Create zephyr LoRA files with added tokens once per test session."""
+    import shutil
+    from tempfile import TemporaryDirectory
+
+    from transformers import AutoTokenizer
+
+    tmp_dir = TemporaryDirectory()
+    tmp_model_dir = f"{tmp_dir.name}/zephyr"
+    shutil.copytree(zephyr_lora_files, tmp_model_dir)
+    tokenizer = AutoTokenizer.from_pretrained("HuggingFaceH4/zephyr-7b-beta")
+    # Copy tokenizer to adapter and add some unique tokens
+    # 32000, 32001, 32002
+    added = tokenizer.add_tokens(["vllm1", "vllm2", "vllm3"],
+                                 special_tokens=True)
+    assert added == 3
+    tokenizer.save_pretrained(tmp_model_dir)
+    yield tmp_model_dir
+    tmp_dir.cleanup()