chore: dependabot upgrade setup-python to 6.0.0

Author: rouilj

.github/workflows/build-xapian.yml

@@ -46,7 +46,7 @@ jobs:
 
         # Setup version of Python to use
       - name: Set Up Python 3.13
-        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
+        uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
           python-version: 3.13
           allow-prereleases: true

.github/workflows/ci-test.yml

@@ -120,7 +120,7 @@ jobs:
 
       # Setup version of Python to use
       - name: Set Up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5.6.0
+        uses: actions/setup-python@e797f83bcb11b83ae66e0230d6156d7c80228e7c # v6.0.0
         with:
           python-version: ${{ matrix.python-version }}
           allow-prereleases: true