docs: add Trivy scan badges

README.md

@@ -44,7 +44,7 @@ The Python template uses some global configuration used throughout all jobs.
 
 | Input / Variable     | Description                                                                           | Default value      |
 | -------------------- | ------------------------------------------------------------------------------------- | ------------------ |
-| `image` / `PYTHON_IMAGE` | The Docker image used to run Python <br/>:warning: **set the version required by your project** | `registry.hub.docker.com/library/python:3-slim` |
+| `image` / `PYTHON_IMAGE` | The Docker image used to run Python <br/>:warning: **set the version required by your project** | `registry.hub.docker.com/library/python:3-slim` <br/>[![Trivy Badge](https://to-be-continuous.gitlab.io/doc/secu/trivy-badge-PYTHON_IMAGE.svg)](https://to-be-continuous.gitlab.io/doc/secu/trivy-PYTHON_IMAGE) |
 | `project-dir` / `PYTHON_PROJECT_DIR` | Python project root directory                                                         | `.`                |
 | `build-system` / `PYTHON_BUILD_SYSTEM`| Python build-system to use to install dependencies, build and package the project (see below) | `auto` (auto-detect) |
 | `PIP_INDEX_URL`      | Python repository url                                                                 | _none_             |