Implement endpoint "GET /tasks/service-info"

[uniqueg]

Is your feature request related to a problem? Please describe. proTES should respond to all TES requests in the most reasonable or helpful way in a spec-conformant way.

In the case of the GET /tasks/service-info endpoint, this simply means to return the service info from the database.

Describe the solution you'd like Add service info parameters to the config file and load them to the database upon starting the service (refresh upon restart). Upon receiving the request, return the service info from the database. The solution is almost identical to that for the /service-info endpoint in WES-ELIXIR, implemented in files:

• https://github.com/elixir-europe/WES-ELIXIR/blob/dev/wes_elixir/ga4gh/wes/server.py
• https://github.com/elixir-europe/WES-ELIXIR/blob/dev/wes_elixir/ga4gh/wes/endpoints/get_service_info.py
• https://github.com/elixir-europe/WES-ELIXIR/blob/dev/wes_elixir/database/register_mongodb.py

Describe alternatives you've considered N/A

Additional context Depends on issue #17 being resolved.