[Docs] Align fd code lines with Flytesnacks examples

[JiangJiaWei1103]

Tracking issue

NA

Why are the changes needed?

Due to the transition from rli to literalinclude, two code snippets on FlyteDirectory page are out of sync of the following two Flytesnacks examples, folder.py and file_streaming.py.

What changes were proposed in this pull request?

Align code snippets on the doc page with two corresponding examples.

Check all the applicable boxes

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

Related PRs

#6008

Docs link

https://flyte--6149.org.readthedocs.build/en/6149/user_guide/data_types_and_io/flytedirectory.html

[flyte-bot]

Code Review Agent Run Status

• Limitations and other issues: ❌ Failure - The AI Code Review Agent skipped reviewing this change because it is configured to exclude certain pull requests based on the source/target branch or the pull request status. You can change the settings here, or contact the agent instance creator at eduardo@union.ai.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 37.02%. Comparing base (27c9edd) to head (1520498).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #6149   +/-   ##
=======================================
  Coverage   37.01%   37.02%           
=======================================
  Files        1317     1317           
  Lines      132523   132523           
=======================================
+ Hits        49060    49066    +6     
+ Misses      79217    79211    -6     
  Partials     4246     4246           

Flag	Coverage Δ
unittests-datacatalog	51.58% <ø> (ø)
unittests-flyteadmin	54.25% <ø> (+0.02%)	⬆️
unittests-flytecopilot	30.99% <ø> (ø)
unittests-flytectl	62.29% <ø> (ø)
unittests-flyteidl	7.23% <ø> (ø)
unittests-flyteplugins	53.85% <ø> (ø)
unittests-flytepropeller	42.64% <ø> (ø)
unittests-flytestdlib	55.18% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.