COMP: Update Python package builds to v6.0b01.post1

With XCode 16.2 for compatibility.

Author: thewtex

.github/workflows/build-test-package-python.yml

@@ -13,14 +13,14 @@ on:
         description: 'Github release version tag for the ITKPythonBuilds build archive to use'
         required: false
         type: string
-        default: 'v6.0b01'
+        default: 'v6.0b01.post1'
       itk-python-package-tag:
         # See https://github.com/InsightSoftwareConsortium/ITKPythonPackage
         description: 'Git tag or commit hash for ITKPythonPackage build scripts to use'
         required: false
         type: string
         # v6.0b01
-        default: 'v6.0b01'
+        default: 'v6.0b01.post1'
       itk-python-package-org:
         description: 'Github organization name for fetching ITKPythonPackage build scripts'
         required: false