Add timeseries plotting

[SavvasMel]

Description

With this PR, we allow plotting of timeseries per variable and sample. Example use:

default_streams:
  ERA5:
    regions: ["global"]
    channels: ["2t", "10u"] #, "10v", "z_500", "t_850", "u_850", "v_850", "q_850", ]
    evaluation:
      forecast_step: "all"
      sample: "all"
    plotting:
      sample: "all"
      forecast_step: "all" #supported: "all", [1,2,3,...], "1-50" (equivalent of [1,2,3,...50])
      plot_maps: false
      plot_bias: false
      plot_target: false
      plot_histograms: false
      plot_animations: false
      plot_timeseries: true        <--------------------------

Issue Number

Closes #1933

Is this PR a draft? Mark it as draft.

Checklist before asking for review

• I have performed a self-review of my code
• My changes comply with basic sanity checks:
  • I have fixed formatting issues with ./scripts/actions.sh lint
  • I have run unit tests with ./scripts/actions.sh unit-test
  • I have documented my code and I have updated the docstrings.
  • I have added unit tests, if relevant
• I have tried my changes with data and code:
  • I have run the integration tests with ./scripts/actions.sh integration-test
  • (bigger changes) I have run a full training and I have written in the comment the run_id(s): launch-slurm.py --time 60
  • (bigger changes and experiments) I have shared a hegdedoc in the github issue with all the configurations and runs for this experiments
• I have informed and aligned with people impacted by my change:
  • for config changes: the MatterMost channels and/or a design doc
  • for changes of dependencies: the MatterMost software development channel

[SavvasMel]

[iluise]

Thanks for implementing this. I tested it and it works very well. I added some style comments to make it more compact

[iluise]

Approving it, Savvas can you add the plot_timeseries flag to the config?

I tested it on ATOS and I get these warnings:

In a future version of xarray the default value for coords will change from coords='different' to coords='minimal'. This is likely to lead to different results when multiple datasets have matching variables with overlapping values. To opt in to new defaults and get rid of these warnings now use `set_options(use_new_combine_kwarg_defaults=True) or set coords explicitly.
  xr.concat(preds_steps, dim="forecast_step"),
/etc/ecmwf/nfs/dh2_home_a/ecm9336/WeatherGenerator/packages/evaluate/src/weathergen/evaluate/plotting/timeseries.py:58: FutureWarning: In a future version of xarray the default value for coords will change from coords='different' to coords='minimal'. This is likely to lead to different results when multiple datasets have matching variables with overlapping values. To opt in to new defaults and get rid of these warnings now use `set_options(use_new_combine_kwarg_defaults=True) or set coords explicitly.
  xr.concat(preds_steps, dim="forecast_step"),
/etc/ecmwf/nfs/dh2_home_a/ecm9336/WeatherGenerator/packages/evaluate/src/weathergen/evaluate/plotting/timeseries.py:59: FutureWarning: In a future version of xarray the default value for coords will change from coords='different' to coords='minimal'. This is likely to lead to different results when multiple datasets have matching variables with overlapping values. To opt in to new defaults and get rid of these warnings now use `set_options(use_new_combine_kwarg_defaults=True) or set coords explicitly.
  xr.concat(tars_steps, dim="forecast_step"),
/etc/ecmwf/nfs/dh2_home_a/ecm9336/WeatherGenerator/packages/evaluate/src/weathergen/evaluate/plotting/timeseries.py:59: FutureWarning: In a future version of xarray the default value for coords will change from coords='different' to coords='minimal'. This is likely to lead to different results when multiple datasets have matching variables with overlapping values. To opt in to new defaults and get rid of these warnings now use `set_options(use_new_combine_kwarg_defaults=True) or set coords explicitly.
  xr.concat(tars_steps, dim="forecast_step"),
[Parallel(n_jobs=2)]: Done 2 out of 2 | elapsed:    4.8s finished

Can you take a look?