chore: fix annoying python CI/CD errors due to unsuported action (#473)

* chore: fix annoying python CI/CD errors due to unsuported action

* cache uv deps

* cache pyproject.toml

* Use setup-uv action pinned to commit SHA instead of pip install

Replace `pip install uv` with `astral-sh/setup-uv` pinned to commit
SHA for supply chain security. Remove redundant manual uv cache step
as setup-uv handles caching natively.

---------

Co-authored-by: Keith Lee <leekei@apache.org>

Author: fresh-borzoni

.github/workflows/build_and_test_python.yml

@@ -53,7 +53,7 @@ jobs:
           python-version: ${{ matrix.python }}
 
       - name: Install uv
-        uses: astral-sh/setup-uv@v4
+        uses: astral-sh/setup-uv@37802adc94f370d6bfd71619e3f0bf239e1f3b78
 
       - name: Install protoc
         run: sudo apt-get update && sudo apt-get install -y protobuf-compiler