added qwen1.5-7b to model list (openvinotoolkit#316)

I've verified support of Qwen1.5-7B by OpenVINO and then added it to the
github workflow and readme.md
```
(base) root@8tvt:~/openvino.genai/llm_bench/python# ../../text_generation/causal_lm/cpp/build/greedy_causal_lm qwen/pytorch/dldt/FP32/ "Why is the Sun yellow?"

 

The Sun does not actually appear yellow to us when we look at it. In fact, it appears white because it emits light across a wide range of wavelengths, including all the colors of the visible spectrum. When this light reaches our eyes, our eyes combine the different colors to create the perception of white.
```

---------

Co-authored-by: Pavel Esir <pavel.esir@gmail.com>

Author: mengbingrock

.github/workflows/causal_lm_cpp.yml

@@ -192,6 +192,32 @@ jobs:
           source ./ov/setupvars.sh
           convert_tokenizer ./Qwen-7B-Chat/pytorch/dldt/FP16/ --output ./Qwen-7B-Chat/pytorch/dldt/FP16/ --with-detokenizer --trust-remote-code
           timeout 50s ./build/beam_search_causal_lm ./Qwen-7B-Chat/pytorch/dldt/FP16/ 69 > ./pred.txt
+  cpp-beam_search_causal_lm-Qwen1_5-7B-Chat:
+    runs-on: ubuntu-20.04-16-cores
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: recursive
+      - uses: actions/setup-python@v4
+        with:
+          python-version: 3.8
+      - name: Install OpenVINO
+        run: |
+          mkdir ./ov/
+          curl https://storage.openvinotoolkit.org/repositories/openvino/packages/nightly/2024.1.0-14645-e6dc0865128/l_openvino_toolkit_ubuntu20_2024.1.0.dev20240304_x86_64.tgz | tar --directory ./ov/ --strip-components 1 -xz
+          sudo ./ov/install_dependencies/install_openvino_dependencies.sh
+      - name: Download, convert and build
+        run: |
+          source ./ov/setupvars.sh
+          python -m pip install --upgrade-strategy eager "optimum>=1.14" -r ./llm_bench/python/requirements.txt ./thirdparty/openvino_tokenizers/[transformers] --extra-index-url https://download.pytorch.org/whl/cpu && python ./llm_bench/python/convert.py --model_id Qwen/Qwen1.5-7B-Chat --output_dir ./Qwen1.5-7B-Chat/ --precision FP16 &
+          cmake -DCMAKE_BUILD_TYPE=Release -S ./text_generation/causal_lm/cpp/ -B ./build/
+          cmake --build ./build/ --config Release -j
+          wait
+      - name: Run
+        run: |
+          source ./ov/setupvars.sh
+          convert_tokenizer ./Qwen1.5-7B-Chat/pytorch/dldt/FP16/ --output ./Qwen1.5-7B-Chat/pytorch/dldt/FP16/ --with-detokenizer --trust-remote-code
+          timeout 50s ./build/beam_search_causal_lm ./Qwen1.5-7B-Chat/pytorch/dldt/FP16/ "你好！" > ./pred_qwen15.txt
   cpp-beam_search_causal_lm-Phi-2:
     runs-on: ubuntu-20.04-16-cores
     steps:

text_generation/causal_lm/cpp/README.md

@@ -130,6 +130,8 @@ To enable Unicode characters for Windows cmd open `Region` settings from `Contro
 6. Qwen
    1. https://huggingface.co/Qwen/Qwen-7B-Chat
    2. https://huggingface.co/Qwen/Qwen-7B-Chat-Int4 - refer to
+   3. https://huggingface.co/Qwen/Qwen1.5-7B-Chat
+   4. https://huggingface.co/Qwen/Qwen1.5-7B-Chat-GPTQ-Int4
    [Qwen-7B-Chat-Int4 - Torch not compiled with CUDA enabled](../../../llm_bench/python/doc/NOTES.md#qwen-7b-chat-int4---torch-not-compiled-with-cuda-enabled)
    in case of `AssertionError`
 7. Dolly