Remove ICGC25k Dockerfile and Song Server Configuration from Codebase

[Azher2Ali]

Summary of request

This PR removes the Dockerfile.icgc25k and associated Song Server configuration from the codebase. The ICGC25k-specific components are no longer relevant, and their removal is part of the ongoing effort to eliminate outdated ICGC-related traces from the project. This helps streamline the setup and avoids unnecessary dependencies

Desired solution

The desired solution is to completely remove the Dockerfile.icgc25k from the repository, along with any related configurations or dependencies specific to the ICGC25k project. This will ensure that the codebase is free from obsolete ICGC traces, resulting in a cleaner, more maintainable setup that focuses solely on the currently supported environments and configurations.

Additional context

Include any relevant context or screenshots regarding your request here.

https://github.com/overture-stack/SONG/blob/develop/Dockerfile.icgc25k#L2