Use NumPy 1.19.5 for building the wheels

[antalszava]

• The PennyLane-Lightning binaries are now built with NumPy 1.19.5, to avoid ABI
  compatibility issues with the latest NumPy 1.20 release. See
  the NumPy release notes
  for more details.
• Prepares the 1.15.1 release

[codecov]

Codecov Report

Merging #97 (da777f6) into master (b0910bc) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master      #97   +/-   ##
=======================================
  Coverage   98.14%   98.14%           
=======================================
  Files           3        3           
  Lines          54       54           
=======================================
  Hits           53       53           
  Misses          1        1           

Impacted Files	Coverage Δ
pennylane_lightning/_version.py	100.00% <100.00%> (ø)

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[josh146]

Hey @antalszava, you'll need to explicitly modify the actions to ensure that numpy==1.19.5 is installed for building the wheels :) We can't leave the NumPy version used to build the wheels unpinned.

[antalszava]

Hi @josh146, looks like it builds well, right?

Some parts of the Ubuntu wheel build log:

https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:86
https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:181
https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:263
https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:356
https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:438
https://github.com/PennyLaneAI/pennylane-lightning/pull/97/checks?check_run_id=2469564387#step:6:527

[josh146]

Thanks @antalszava 💯