Support snapshots in DefaultQubit2

[eddddddy]

Basically port over the implementation from DefaultQubit and add a couple of tests.

[github-actions]

Hello. You may have forgotten to update the changelog!
Please edit doc/releases/changelog-dev.md with:

• A one-to-two sentence description of the change. You may include a small working example for new features.
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[codecov]

Codecov Report

Merging #4193 (2ec0a87) into master (a7ae25b) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #4193   +/-   ##
=======================================
  Coverage   99.77%   99.77%           
=======================================
  Files         342      342           
  Lines       30709    30737   +28     
=======================================
+ Hits        30639    30667   +28     
  Misses         70       70           

Impacted Files	Coverage Δ
pennylane/ops/functions/dot.py	100.00% <ø> (ø)
pennylane/pulse/__init__.py	100.00% <ø> (ø)
pennylane/pulse/rydberg.py	100.00% <ø> (ø)
pennylane/pulse/transmon.py	100.00% <ø> (ø)
pennylane/_qubit_device.py	99.29% <100.00%> (+<0.01%)	⬆️
pennylane/debugging.py	100.00% <100.00%> (ø)
pennylane/devices/experimental/default_qubit_2.py	100.00% <100.00%> (ø)
pennylane/devices/qubit/apply_operation.py	100.00% <100.00%> (ø)
pennylane/devices/qubit/preprocess.py	100.00% <100.00%> (ø)
pennylane/devices/qubit/simulate.py	100.00% <100.00%> (ø)
... and 2 more

[albi3ro]

Was testing it out with code from #4196 , and the preprocessing was decomposing the snapshots away. We need to edit preprocess.py line 56 to manually specify that the new device support snapshots.

[eddddddy]

@albi3ro Can you check if the last change was what you meant?

[albi3ro]

Looks good 👍 I'm happy with this :)

[eddddddy]

[sc-33774]