Update build_pipeline.yml

Upgrade the cache action in the build pipeline

Author: mfitz

.github/workflows/build_pipeline.yml

@@ -12,7 +12,7 @@ jobs:
     - uses: actions/setup-python@v5
       with:
         python-version: 3.11
-    - uses: actions/cache@v1
+    - uses: actions/cache@v4
       with:
         path: ~/.cache/pip
         key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}