Update docker Docker tag to v29 (#5923)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| docker | docker | major | `28` → `29` |

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Reviewed-on: #5923
Co-authored-by: Renovate Bot <admin@fsfe.org>
Co-committed-by: Renovate Bot <admin@fsfe.org>

.drone.yml

@@ -8,7 +8,7 @@ clone:
 
 steps:
   - name: pre-commit
-    image: docker:28
+    image: docker:29
     environment:
       # Environment variables necessary for rootless Docker
       XDG_RUNTIME_DIR: "/run/user/1001"
@@ -28,7 +28,7 @@ steps:
 
   # Test building the deploy docker image
   - name: test-build-docker-image
-    image: docker:28
+    image: docker:29
     environment:
       # Environment variables necessary for rootless Docker
       XDG_RUNTIME_DIR: "/run/user/1001"
@@ -59,7 +59,7 @@ steps:
         - deployment
 
   - name: deploy-master
-    image: docker:28
+    image: docker:29
     environment:
       # Environment variables necessary for rootless Docker
       XDG_RUNTIME_DIR: "/run/user/1001"
@@ -93,7 +93,7 @@ steps:
           - pull_request
 
   - name: deploy-test
-    image: docker:28
+    image: docker:29
     environment:
       # Environment variables necessary for rootless Docker
       XDG_RUNTIME_DIR: "/run/user/1001"