Better ASV Pixi integration

[VeckoTheGecko]

I think this PR results in better Pixi/ASV integration - where ASV (when providing asv run --python=same) uses the same Pixi installation as in benchmarks pixi environment.

If you want to use a different Parcels installation to run the benchmarks, it should be a simple one line update in pixi.toml from

diff --git a/pixi.toml b/pixi.toml
index 7f964c0..5afba7a 100644
--- a/pixi.toml
+++ b/pixi.toml
@@ -22,7 +22,7 @@ python = ">=3.12"
 intake-xarray = "*"
 py-rattler = "0.15.*"
 asv = ">=0.6.5"
-parcels = { path = "./Parcels" }
+parcels = { path = "/Users/Hodgs004/coding/repos/parcels" } # e.g.
 
 
 [tasks]

This workflow is working well for me. Feel free to give it a spin @erikvansebille and if it works well for you, we can merge into main. This can also wait until you're back from EGU.

[VeckoTheGecko]

(most of the diff is from the lockfile, which changed significantly because we chance how we install Parcels here)

[erikvansebille]

Yep, this new Pixi workflow seems to work for me! Very nice that I can link to another Parcels pro this way. So do we still need the submodule here?

[erikvansebille]

Do we need the Parcels submodule, or ask users to link to their local Parcels repo by default?

[VeckoTheGecko]

I think having the Parcels submodule is best - but users can definitely override this locally if they want to for debugging. They can even directly modify the submodule and contribute back that way if they want to