NIFI-14100: Add option to sequential download of dependencies for Pyt…

[Lehel44]

…hon processors

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NIFI-14100

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[exceptionfactory]

@Lehel44 Thanks for highlighting this issue, but I don't think the proposed approach is a good way forward.

This is not something an administrator should have to configure, and we should avoid introducing new configuration properties if we can implement better behavior in general.

There are inherent limitations with automatic dependency downloads for Python, which is one of the reasons for introducing Python-based NAR bundling. That should be the solution for resource-constrained environments.

We may be able to improve download behavior by replacing pip with uv, although that is a system requirement to consider.

As it stands, we should further consider the options before pursuing the current approach.