Add term entry for .getdata() method in Pillow

[TanyaDyakonova]

Description

Created a new term entry for the .getdata() method from the Pillow library.

• File: docs/content/pillow/concepts/image/terms/getdata/getdata.md
• Includes a description of the method, syntax, and an example.
• An output image (pillow_getdata_sample.jpg) was added to docs/media/ to visually demonstrate .getdata() in action.
  This addition is part of the Pillow image concept terms project.

Issue Solved

Closes #6520

Type of Change

Adding a new entry

Checklist

• [+] All writings are my own.
• [+] My entry follows the Codecademy Docs style guide.
• [+] My changes generate no new warnings.
• [+] I have performed a self-review of my own writing and code.
• [+] I have checked my entry and corrected any misspellings.
• [+] I have made corresponding changes to the documentation if needed.
• [+] I have confirmed my changes are not being pushed from my forked main branch.
• [+] I have confirmed that I'm pushing from a new branch named after the changes I'm making.
• [+] I have linked any issues that are relevant to this PR in the Issues Solved section.

[CLAassistant]

All committers have signed the CLA.

[mamtawardhani]

Hey @TanyaDyakonova, the entry looks perfect! 😄

Just one change is needed, could you please use a different image in the example, and place that image in the media folder in docs. Thank you!

[mamtawardhani]

Hey @TanyaDyakonova could you please work on the above suggestion? Thank you! 😄

[TanyaDyakonova]

Hi @mamtawardhani , thanks for the suggestion!
✅ I've updated the image and the example output as requested. Please let me know if anything else needs to be adjusted. 😊

[mamtawardhani]

Looks good for a second round of review! 🚀