EZESC-1933 -Update pi.yaml to remove duplicate volume

[abe-hpe]

Fixes for the Pi example to remove duplicate volume (same issue and fix as for the wordcount example described in EZESC-1933, and discussed with Mayank, Simhan and others)

Provide a clear and concise description of the content changes you're proposing. List all the changes you are making
to the content.

• Updated section ___ with ___.
• Added new subsection ___ under ___.
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Closes #...

If there is no issue related to this PR, kindly create one first to describe the motivation behind these changes.

Checklist:

• I have checked that my enhancements are not duplicates of existing content changes or additions.
• I have tested the changes in a working environment to ensure they function as intended.
• I have followed the style guide
  outlined in the contribution guidelines.

Reviewer's Tasks (for maintainers reviewing this PR):

• Verify that the tutorial functions correctly in a live environment.
• Verify that the updated content aligns with the style guide
  in the contribution guidelines.
• Check for consistency, grammar, and clarity throughout the updated content.
• Check that the related GitHub issue is up-to-date.