Update selenium.version to v4.15.0

This MR contains the following updates:

Package	Type	Update	Change
org.seleniumhq.selenium:selenium-support (source)	test	minor	4.13.0 -> 4.15.0
org.seleniumhq.selenium:selenium-firefox-driver (source)	test	minor	4.13.0 -> 4.15.0
org.seleniumhq.selenium:selenium-api (source)	test	minor	4.13.0 -> 4.15.0

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