Open up Pillow again after 7.1.*

[tlambert03]

Description

@jni mentioned that he prefers blocking specific versions, and the Pillow issues are going to be fixed in version ≥7.2.0 (fixed in python-pillow/Pillow#4528), so this PR just restricts Pillow to != 7.1.*

Type of change

• dependencies

How has this been tested?

I ran our test suite and some examples on Pillow 7.2.0.dev and everything works

[sofroniewn]

LGTM!

[codecov]

Codecov Report

Merging #1146 into master will increase coverage by 0.16%.
The diff coverage is 98.50%.

@@            Coverage Diff             @@
##           master    #1146      +/-   ##
==========================================
+ Coverage   87.02%   87.18%   +0.16%     
==========================================
  Files         221      221              
  Lines       19459    19672     +213     
==========================================
+ Hits        16935    17152     +217     
+ Misses       2524     2520       -4     

Impacted Files	Coverage Δ
napari/layers/image/image.py	92.63% <85.71%> (-0.31%)	⬇️
napari/layers/points/points.py	93.64% <96.51%> (+0.48%)	⬆️
napari/_qt/layers/qt_image_layer.py	95.08% <100.00%> (-0.04%)	⬇️
napari/_tests/test_viewer.py	93.90% <100.00%> (+1.14%)	⬆️
napari/_tests/utils.py	100.00% <100.00%> (ø)
napari/_vispy/vispy_base_layer.py	97.05% <100.00%> (+0.21%)	⬆️
napari/_vispy/vispy_image_layer.py	84.09% <100.00%> (-0.36%)	⬇️
napari/_vispy/vispy_points_layer.py	90.62% <100.00%> (+0.30%)	⬆️
napari/_vispy/vispy_shapes_layer.py	92.30% <100.00%> (+0.30%)	⬆️
napari/_vispy/vispy_surface_layer.py	90.47% <100.00%> (+0.47%)	⬆️
... and 5 more

---

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 6ea95a9...6532c36. Read the comment docs.