chore: Bump canonical/charming-actions in the github_actions group

Bumps the github_actions group with 1 update: [canonical/charming-actions](https://github.com/canonical/charming-actions).


Updates `canonical/charming-actions` from 2.5.0.pre.rc to 2.6.0
- [Release notes](https://github.com/canonical/charming-actions/releases)
- [Commits](canonical/charming-actions@2.5.0-rc...2.6.0)

---
updated-dependencies:
- dependency-name: canonical/charming-actions
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: github_actions
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/promote.yaml

@@ -33,7 +33,7 @@ jobs:
             echo "promote-to=stable" >> ${GITHUB_ENV}
           fi
       - name: Promote Charm
-        uses: canonical/charming-actions/release-charm@2.5.0-rc
+        uses: canonical/charming-actions/release-charm@2.6.0
         with:
           base-channel: 22.04
           credentials: ${{ secrets.CHARMCRAFT_AUTH }}

.github/workflows/publish-charm.yaml

@@ -26,11 +26,11 @@ jobs:
         run: echo "charm_path=$(find . -name '*.charm' -type f -print)" >> $GITHUB_OUTPUT
 
       - name: Select Charmhub channel
-        uses: canonical/charming-actions/channel@2.5.0-rc
+        uses: canonical/charming-actions/channel@2.6.0
         id: channel
 
       - name: Upload charm to Charmhub
-        uses: canonical/charming-actions/upload-charm@2.5.0-rc
+        uses: canonical/charming-actions/upload-charm@2.6.0
         with:
           built-charm-path: ${{ steps.charm-path.outputs.charm_path }}
           credentials: "${{ secrets.CHARMCRAFT_AUTH }}"