Previously, the configuration processor would ignore any
@ConfigurationProperties-annotated methods that were not public. This
prevented metadata generation for package-private @Bean methods such
as those in DataSourceConfiguration's inner-classes for DBCP2, Hikari,
and Tomcat JDBC.
This commit updates the annotation processor so that it will process
any non-private method annotated with @ConfigurationProperties.
Fixes gh-18124
4b5ebd8505