Feature/181713000 pick the default plot type and parameter values from the backend

[upendrakumbham]

Ann data feature:

• Fetches the default plot type and its corresponding parameterisation values from the DB.
• SQL query finds the highest value of the priority column per each plot type, fetches that plot type and the corresponding parameterisation as a default.
• Endpoint /json/cell-plots/{experimentAccession}/default/plot-method
• Associated PR - atlas-web-core

Note: This story has a dependency - we need to merge this PR once we merge migrate-to-schema-v19. Otherwise, Jenkins build will break due to legacy code with latest schema.

Here is the final output : {umap={"n_neighbors":15}, tsne={"perplexity":20}}

[upendrakumbham]

Hi @lingyun1010, I have fixed your review comments, please have a look.

[lingyun1010]

The default plot method and parameterisation could be passed into the tsne plot component as part of the content in ExperimentPageContentService, so please consider if we still need an endpoint for that.

[lingyun1010]

Please also keep the json reponse as the format like defaultPlotTypeAndParameterisation: {"t-SNE": {"perplexity": 50}, "UMAP": {"n_neighbors": 100}}, the same as the props plotTypesAndOptions, so we could have consistent parsing method in the front-end. FYI, currently the json reponse from the endpoint is {"t-SNE":"{\"perplexity\": 50}","UMAP":"{\"n_neighbors\": 100}"}.