Add LGPL v3 license notice to docs/README.rst and specify LICENSE.txt in pyproject.toml

Author: chenyunliang520

docs/README.rst

@@ -3,6 +3,16 @@
 GaussDB documentation build
 ===========================
 
+.. note::
+
+   **License**: This documentation is part of the **gaussdb** project and is licensed under the
+   `GNU Lesser General Public License v3.0 (LGPL v3)`_.
+
+   See the :download:`LICENSE.txt <../LICENSE.txt>` file in the project root for details.
+
+.. _GNU Lesser General Public License v3.0 (LGPL v3): https://www.gnu.org/licenses/lgpl-3.0.en.html
+
+
 Quick start::
 
     make env

pyproject.toml

@@ -2,6 +2,10 @@
 requires = ["setuptools>=49.2.0", "wheel>=0.37"]
 build-backend = "setuptools.build_meta"
 
+[project]
+name = "gaussdb"
+license = { file = "LICENSE.txt" }
+
 [tool.pytest.ini_options]
 addopts = "-ra"
 filterwarnings = [