Only transform the literal that matches the map task index

[EngHabu]

Tracking issue

fixes flyteorg/flyte#5483

Why are the changes needed?

Existing code only trims map task inputs before invoking the python subtask. This is incorrect as it leads to flytekit unnecessarily downloading all inputs for the entire maptask (potentially 10s of thousands) for each subtask.

What changes were proposed in this pull request?

For local execution, continue with the current behavior of handling all subtasks inputs when the map task is invoked.
For remote execution, index into the inputs list using the maptask index and only transform this input.

How was this patch tested?

• Ran tests locally
• Stepped through the code to make sure it correctly computes the interface, trims inputs... etc.
• Ran a 3k map task job remotely and looked into logs before and after to confirm it no longer attempts to download all inputs

Setup process

Screenshots

Check all the applicable boxes

• I updated the documentation accordingly.
• All new and existing tests passed.
• All commits are signed-off.

[codecov]

Codecov Report

Attention: Patch coverage is 13.63636% with 19 lines in your changes missing coverage. Please review.

Project coverage is 50.98%. Comparing base (8562fd9) to head (188a7bf).
Report is 4 commits behind head on master.

❗ Current head 188a7bf differs from pull request most recent head 1fbc324

Please upload reports for the commit 1fbc324 to get more accurate results.

Files	Patch %	Lines
flytekit/core/array_node_map_task.py	13.63%	19 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           master    #2484       +/-   ##
===========================================
- Coverage   73.97%   50.98%   -23.00%     
===========================================
  Files         250      185       -65     
  Lines       21592    18677     -2915     
  Branches     3644     3645        +1     
===========================================
- Hits        15973     9522     -6451     
- Misses       4973     8674     +3701     
+ Partials      646      481      -165     

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