Outdated string documentation in `io.read_spikeglx()`

[h-mayorquin]

The following link in the documentation seems broken.

probeinterface/probeinterface/io.py

Line 715 in 196f203

# https://github.com/billkarsh/SpikeGLX/blob/gh-pages/Support/Metadata_30.md#channel-entries-by-type

@samuelgarcia

[samuelgarcia]

oups.
thanks I will have a look.

[alejoe91]

seems fixed! :)