Cast array gate parameters to list

[antalszava]

Context

With the release of Qiskit 0.23.3 gate parameters cannot be arrays. This PR adds conversion from arrays to lists.

Note

This PR makes the device tests pass for the plugin.

[codecov]

Codecov Report

Merging #126 (e251076) into master (dfbf988) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #126   +/-   ##
=======================================
  Coverage   99.30%   99.30%           
=======================================
  Files           7        7           
  Lines         286      289    +3     
=======================================
+ Hits          284      287    +3     
  Misses          2        2           

Impacted Files	Coverage Δ
pennylane_qiskit/qiskit_device.py	100.00% <100.00%> (ø)

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