MAINT: remove pyproject.toml

[saketkc]

Based on @grlee77's comment.
Also, see scipy/scipy#8735

[codecov-io]

Codecov Report

Merging #366 into master will decrease coverage by 0.23%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #366      +/-   ##
==========================================
- Coverage   83.78%   83.55%   -0.24%     
==========================================
  Files          21       21              
  Lines        3251     3332      +81     
  Branches      537      567      +30     
==========================================
+ Hits         2724     2784      +60     
- Misses        466      484      +18     
- Partials       61       64       +3

Impacted Files	Coverage Δ
pywt/_extensions/c/wt.template.c	87.38% <0%> (-7.78%)	⬇️
pywt/_extensions/c/common.c	94.44% <0%> (-5.56%)	⬇️
pywt/_extensions/c/wavelets.c	85.74% <0%> (-1.39%)	⬇️
pywt/_extensions/c/convolution.template.c	97.48% <0%> (-1.22%)	⬇️
pywt/_wavelet_packets.py	78.12% <0%> (ø)	⬆️
pywt/_extensions/c/cwt.template.c	97.89% <0%> (+0.04%)	⬆️
pywt/_utils.py	80.76% <0%> (+15.38%)	⬆️
pywt/__init__.py	96.15% <0%> (+19.23%)	⬆️

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[grlee77]

Thanks. This seems to have fixed the issue, but I will leave open for a bit to see if there is any other feedback.

[rgommers]

Makes sense. These issues will likely be fixed in pip before long; we can then add it back.