[Docker] Update docker images used within the codebase

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

## Disclaimer

This is probably very difficult to implement given all the different files these could be stored. I am logging it to hear your thoughts and to see if there are possible ways to do this

## Background

While using [testcontainers](https://www.testcontainers.org/), it is common to define docker images using the following syntax:

```java

// Referring directly to an image on Docker Hub (mysql:8.0.24)
final MySQLContainer mysql = new MySQLContainer<>(
DockerImageName.parse("mysql:8.0.24")
)

final MySQLContainer mysql = new MySQLContainer<>(
DockerImageName.parse("registry.mycompany.com/mirror/mysql:8.0.24")
.asCompatibleSubstituteFor("mysql")
)

```

It would be ideal if dependabot could detect and update them

if parsing all files is too expensive, maybe we could configure specific files to scan.

No files, tests, or entry points are named. Start by searching the repository for DockerImageName.parse and the testcontainers examples in the issue, then map where image references are stored and how Dependabot currently discovers them. Done means Dependabot can detect and propose updates for supported Docker image references, with an agreed approach for limiting scanned files if needed.

Written by the indexing model from the issue text.