Update precommit.yml

Author: jagapiou

.github/workflows/precommit.yml

@@ -57,11 +57,10 @@ jobs:
         if: startsWith( matrix.cfg.os, 'macos-' )
         run: |
           brew --version
-          brew install
-              python@${{ matrix.python-version }} \
-              numpy \
-              python-packaging
-          
+          brew install python@${{ matrix.python-version }}
+          brew install python-packaging
+          brew install numpy
+
       - name: show setup
         run: |
           bazel --version