fixed typo in workflow

.github/workflows/release_macos.yml

@@ -20,7 +20,7 @@ jobs:
       run: |
         python -m pip install pip==22.2.2 setuptools==65.3.0
         pip install -r requirements.txt
-        pip install PyInstaller=5.3
+        pip install PyInstaller==5.3
     - name: Build binary
       run: |
         pyinstaller --onefile -n nanovna-saver nanovna-saver.py