fix: ensure tasks are fetched for the best platform

[jjjermiah]

task list was not displaying when targets were specified

manifest-path

[project]
channels = ["https://fast.prefix.dev/conda-forge"]
name = "pixi"
platforms = ["linux-64", "win-64", "osx-64", "osx-arm64"]

[tasks]
make.cmd = "command_1"
generate_keymap.cmd = "command_2"
svg.cmd = "command_3"

[target.osx.tasks]
flash.cmd = "command_4"
port.cmd = "command_5"
port_right.cmd = "command_6"

on osx-arm64

before

> pixi task --manifest-path target/pixi.toml ls -s
Tasks per environment:
----------------------
default: generate_keymap, make, svg

after

> pixi task --manifest-path target/pixi.toml ls -s
Tasks per environment:
----------------------
default: flash, generate_keymap, make, port, port_right, svg

[ruben-arts]

Thanks