Fix for the v-packet logging while parallelism is enabled.

[Rodot-]

Enabling V-Packet logging while the number of threads is set to a value greater than 1 causes the Python kernel to crash. This PR fixes this issue.

The issue stems from trying to append to default Python lists inside a parallel loop in numba (using prange). To avoid multiple threads allocating new memory on the same objects at the same time, I instead cache all vpacket collections ahead of the main loop in a numba typed list. After the main loop, the relevant packet information is extracted back out to create the logging arrays. The vpacket collection caching will always happen even if logging is disabled, but the extraction of the data is not. A potential caveat of this is that there may be more memory usage when a large number of vpackets is requested than normal. This change adds a little less than a second of run time as the instantiation of the vpacket collections and their data retrieval is no longer performed in parallel.

This PR is meant to resolve issue #1614

Motivation and context
The kernel would crash when vpacket logging was enabled with more than 1 thread.

How has this been tested?

• Testing pipeline.
• Ran examples posted in Virtual Logging & Nthreads #1614

Type of change

• Bug fix.
• New feature.
• Breaking change.
• None of the above.

Checklist

• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
  • (optional) I have built the documentation on my fork following the instructions.
• I have assigned and requested two reviewers for this pull request.

[tardis-bot]

Before a pull request is accepted, it must meet the following criteria:

• Is the necessary information provided?
• Is this a duplicate PR?
  • If a new PR is clearly a duplicate, ask how this PR is different from the original PR?
  • If this PR is about to be merged, close the original PR with a link to this new PR that solved the issue.
• Does it pass existing tests and are new tests provided if required?
  • The test coverage should not decrease, and for new features should be close to 100%.
• Is the code tidy?
  • No unnecessary print lines or code comments.

[codecov]

Codecov Report

Merging #1647 (4f52685) into master (7e4631c) will decrease coverage by 0.06%.
The diff coverage is n/a.

❗ Current head 4f52685 differs from pull request most recent head d169166. Consider uploading reports for the commit d169166 to get more accurate results

@@            Coverage Diff             @@
##           master    #1647      +/-   ##
==========================================
- Coverage   67.13%   67.07%   -0.07%     
==========================================
  Files          73       73              
  Lines        6100     6107       +7     
==========================================
+ Hits         4095     4096       +1     
- Misses       2005     2011       +6     

Impacted Files	Coverage Δ
tardis/tardis/montecarlo/montecarlo_numba/base.py	28.73% <0.00%> (-1.27%)	⬇️

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