Quarto: remove manual outdir creation and fix pft outdir

[AritraDey-Dev]

Description

Currently, we don’t need to create the output directory in the demo notebook. This part is leftover from the Demo 1 notebook and has already been removed from Demo 2, since output directory creation is handled by prepare.settings, as mentioned here #3570 (comment).

And also PFT outdir has also been fixed in the settings file, as noted here #3570 (comment).

Motivation and Context

Review Time Estimate

• Immediately
• Within one week
• When possible

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My change requires a change to the documentation.
• My name is in the list of CITATION.cff
• I agree that PEcAn Project may distribute my contribution under any or all of
  • the same license as the existing code,
  • and/or the BSD 3-clause license.
• I have updated the CHANGELOG.md.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.