In order to support Java 22, we must use spring-core 6.1.x.
spring-core 6.1.x is a multi-release jar so, in order to support Java
22, a version of Gradle that supports multi-release jars must be
used.
This commit adds a new variant to spring-boot-gradle-plugin for
modern versions of Gradle. When Gradle's plugin API version is 8.7 or
later, we use spring-core 6.1.x. spring-core 6.0.x is used at all
other times.
Closes gh-40074
c7ec6080ce