関連ワード:  spring boot java 21 support    spring boot 3 java 21 support    spring boot 2.7 java 21 support    spring boot 2 java 21 support    spring boot version support java 21    does spring boot support java 21    does spring boot 2.7 support java 21    does spring boot 2 support java 21    does spring boot 3 support java 21    does spring boot 3.0 support java 21