docs: add oxford comma to support section (@akshattkashyap)

[akshattkashyap]

Description

Added an Oxford comma to the final line in the "Support" section of README.md to improve readability and grammatical consistency.

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Closes #

[Copilot]

Pull request overview

Improves README grammar/readability in the Support section by adding an Oxford comma to the donation sentence.

Changes:

• Add Oxford comma before the final “or” in the Support line in README.md.