chore(deps): update actions/cache action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -32,7 +32,7 @@ jobs:
       - name: Install native dependencies
         run: sudo apt-get update && sudo apt-get -y install libdbus-1-dev libgirepository-2.0-dev libcairo2-dev
       - name: Cache Python packages
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: ~/.cache/pip
           key: lint-code-${{ hashFiles('setup.py') }}-${{ hashFiles('tox.ini') }}
@@ -56,7 +56,7 @@ jobs:
       - name: Install native dependencies
         run: sudo apt-get update && sudo apt-get -y install libdbus-1-dev libgirepository-2.0-dev plantuml libcairo2-dev
       - name: Cache Python packages
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: ~/.cache/pip
           key: docs-${{ hashFiles('setup.py') }}-${{ hashFiles('tox.ini') }}-${{ hashFiles('requirements-doc.txt') }}
@@ -80,7 +80,7 @@ jobs:
       - name: Install native dependencies
         run: sudo apt-get update && sudo apt-get -y install libdbus-1-dev libgirepository-2.0-dev libcairo2-dev
       - name: Cache Python packages
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: ~/.cache/pip
           key: test-mindeps-${{ hashFiles('setup.py') }}-${{ hashFiles('tox.ini') }}
@@ -109,7 +109,7 @@ jobs:
       - name: Install native dependencies
         run: sudo apt-get update && sudo apt-get -y install libdbus-1-dev libgirepository-2.0-dev libcairo2-dev
       - name: Cache Python packages
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: ~/.cache/pip
           key: test-${{ hashFiles('setup.py') }}-${{ hashFiles('tox.ini') }}-${{ matrix.python-version }}
@@ -151,7 +151,7 @@ jobs:
         with:
           node-version: 24
       - name: Cache Node packages
-        uses: actions/cache@v5
+        uses: actions/cache@v6
         with:
           path: node_modules
           key: release-${{ hashFiles('package.json') }}-${{ hashFiles('package-lock.json') }}