Change the UMD global name to `CKEDITOR_REACT`

[filipsobol]

Suggested merge commit message (convention)

Fix: Change the global name used in the UMD build from CKEditor to CKEDITOR_REACT to match the new convention. See ckeditor/ckeditor5#16736.

MINOR BREAKING CHANGE: Change the global name used in the UMD build from CKEditor to CKEDITOR_REACT.

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Additional information

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[coveralls]

Pull Request Test Coverage Report for Build 26a06d71-8c76-47ca-b0af-22e6d6073f86

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 100.0%

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Totals
Change from base Build 1d48e00a-ce42-417a-b0a4-90e80a7dfbde:	0.0%
Covered Lines:	539
Relevant Lines:	539

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💛 - Coveralls