Prior to this commit, if AOP proxy generation was configured with
proxyTargetClass=true (which is the default behavior in recent versions
of Spring Boot), beans implemented as lambda expressions or method
references could not be proxied with CGLIB on Java 16 or higher without
specifying `--add-opens java.base/java.lang=ALL-UNNAMED`.
This commit addresses this shortcoming by ensuring that beans
implemented as lambda expressions or method references are always
proxied using a JDK dynamic proxy even if proxyTargetClass=true.
Closes gh-27971