Conda channels are in wrong order in Windows Tests on Azure

[xhochy]

We currently have

pandas/ci/deps/azure-windows-36.yaml

Lines 2 to 4 in df3d9b2

	channels:
	- defaults
	- conda-forge

for the requirements in the Windows tests. This is sadly a known source for problems as there are conflicting packages in both channels, e.g. boost from defaults and conda-forge is in different packages (libboost vs boost-cpp) and thus both can be installed while one is overriding the other (for boost this is fixed but there are several other packages). See also https://conda-forge.org/docs/user/tipsandtricks.html#multiple-channels for another explanation. The wrong order is probably a source of issues like #23180