Update install instructions

[rob-luke]

Closes #453
Closes #465

[larsoner]

Just minor suggestions, feel free to merge once green @rob-luke !

[codecov]

Codecov Report

Merging #463 (69930bf) into main (8292580) will decrease coverage by 0.18%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #463      +/-   ##
==========================================
- Coverage   96.00%   95.81%   -0.19%     
==========================================
  Files          65       65              
  Lines        2678     2676       -2     
  Branches      343      343              
==========================================
- Hits         2571     2564       -7     
- Misses         50       55       +5     
  Partials       57       57              

Impacted Files	Coverage Δ
mne_nirs/channels/tests/test_roi.py	100.00% <ø> (ø)
mne_nirs/conftest.py	100.00% <ø> (ø)
...rs/datasets/fnirs_motor_group/fnirs_motor_group.py	100.00% <ø> (ø)
mne_nirs/visualisation/_plot_GLM_topo.py	96.37% <ø> (ø)
mne_nirs/io/fold/tests/test_fold.py	100.00% <100.00%> (ø)
mne_nirs/fixes.py	55.55% <0.00%> (-22.23%)	⬇️
mne_nirs/visualisation/_plot_3d_montage.py	98.03% <0.00%> (-0.99%)	⬇️
mne_nirs/statistics/_glm_level_first.py	87.93% <0.00%> (-0.78%)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8292580...69930bf. Read the comment docs.

[larsoner]

This should come back red because mne-tools/mne-python#10630 is not merged yet. Once that's in, I'll restart CIs and hopefully merge once they come back green!

[rob-luke]

Thanks @larsoner
I'll look over this PR again before kicking the ci's and merging.

[larsoner]

All green other than coverage, which I think we can ignore, so I'll go ahead and put this in!

[rob-luke]

Thanks!!