Minor improvements to profiling docs

[dstansby]

• Note that memory_profiler could be useful on Winows, where memray isn't available
• Make memory_profiler orange (from red before). I don't think we should actively discourage using it, even if it is unmaintained at the moment it can still be useful (especially on Windows)
• Split profiling tools up into sub-sections

[paddyroddy]

Is psutil meant to be there twice?

[dstansby]

Woops, I think one of those entries was meant to be pyinstrument. Should be fixed now.

[paddyroddy]

🫐