Dependency conflict mizani/plotnine

[andkay]

There is a dependency conflict which prevents installation of Elara from the requirements file:

ERROR: mizani 0.7.4 has requirement numpy>=1.19.0, but you'll have numpy 1.18.5 which is incompatible.
ERROR: mizani 0.7.4 has requirement pandas>=1.3.5, but you'll have pandas 1.2.1 which is incompatible.

Environment: Python 3.8 on Ubuntu 20.04 LTS

For reference, mizani is a dependency of plotnine (the ggplot2 Python clone), which is only used by the benchmarking module to produce benchmark plots.

Will take care of this, likely in the next sprint.

Immediately, I propose to:

• Bump pandas and run tests
• Remove the explicit numpy dependency, allowing pandas to resolve it.

However, I think we're better off re-writing the plotting functions in matplotlib and removing the plotnine dependency altogether to prevent something like this happening again.