add cicd badges to readme

Author: shunt16

README.md

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 # obsarray: Measurement uncertainty handling in Python
 
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 **obsarray** is an extension to [xarray](https://docs.xarray.dev/en/stable/) for defining, storing and interfacing with uncertainty information using standardised metadata. It is particularly designed to work well with [netCDF](https://www.unidata.ucar.edu/software/netcdf/) files and for the Earth Observation community.
 
 obsarray is part of the [CoMet Toolkit](https://www.comet-toolkit.org) (community metrology toolkit), and can combined with the [punpy](https://punpy.readthedocs.io/en/latest/) (propagating uncertainties in python) module for very simple propagation of defined data uncertainties through arbitrary python functions.