chore(deps): update python docker tag to v3.13.6 (#7148)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| python | stage | patch | `3.13.5-slim-bullseye` ->
`3.13.6-slim-bullseye` |

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dependencies.Dockerfile

@@ -1,4 +1,4 @@
 # This is a renovate-friendly source of Docker images.
-FROM python:3.13.5-slim-bullseye@sha256:846d391e752027be4a490ac42f8bba40b54b8271fd57d18d5304698a02a4efb0 AS python
+FROM python:3.13.6-slim-bullseye@sha256:9c84218d80543ccec094a7e43c7dc69769c9a75c5410d1137a89150f451857f3 AS python
 FROM otel/weaver:v0.16.1@sha256:5ca4901b460217604ddb83feaca05238e2b016a226ecfb9b87a95555918a03af AS weaver
 FROM avtodev/markdown-lint:v1@sha256:6aeedc2f49138ce7a1cd0adffc1b1c0321b841dc2102408967d9301c031949ee AS markdown