Fix upload of Conda package to prefix

[VeckoTheGecko]

Take 2

Continuing #2258

[VeckoTheGecko]

@erikvansebille @fluidnumerics-joe v4 alpha of Parcels has been released

(you might need to push to your respective notebook repos for Binder to invalidate the cache and build a new image)

[erikvansebille]

Huh, it still didn't work, even thought he binder was built again after I pushed an update...

[erikvansebille]

It seems to pick up v3? Is something wrong in the environment file?

>> import parcels
>> print(parcels.__version__)
3.1.3.dev1012

[erikvansebille]

It works! I updated the environment.yaml file to parcels = 4 in Parcels-code/10year-anniversary-session4@fd1b2b2 and the binder now picks up the alpha release

Note that the version number of that release is wrong:

>> import parcels
>> print(parcels.__version__)
0.1.dev1

(not urgent to fix, though)