Visualization of single uncertain time series

[marinaevers]

The uncertain time series should be visualized by showing the mean, the percentiles, and a set of samples, similar to this paper (https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10433771). Therefore, we want a function
def plot_time_series(time_series, n_samples=3, seed=55, fig=None, axs=None, colorblind_safe=False, show_plot=False, **kwargs):,
where time_series is an object of the TimeSeries class. n_samples should be the number for time series samples shown in the plot. The other parameters are consistent with the other plotting functions. The current interface for time series can be found in the corresponding branch.
This plot should show a single uncertain time series but not the covariance matrix. The x-axis should use the time steps.

There should also be an example notebook that creates a time series and then plots it.