Take MethodType into account to deduce main application class

The change in https://github.com/spring-projects/spring-boot/pull/31828 is breaking a native image deployment as follows:

Exception in thread "main" java.lang.UnsupportedOperationException
        at java.lang.StackWalker$StackFrame.getMethodType(StackWalker.java:148)
        at org.springframework.boot.SpringApplication.lambda$findMainClass$1(SpringApplication.java:290)
        at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:178)
        at java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
        at com.oracle.svm.core.jdk.Target_java_lang_StackWalker$AbstractStackFrameSpliterator.tryAdvance(Target_java_lang_StackWalker.java:220)
        at java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:129)
        at java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:527)
        at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:513)
        at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
        at java.util.stream.FindOps$FindOp.evaluateSequential(FindOps.java:150)
        at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
        at java.util.stream.ReferencePipeline.findFirst(ReferencePipeline.java:647)
        at org.springframework.boot.SpringApplication.findMainClass(SpringApplication.java:290)
        at java.lang.StackWalker.walk(StackWalker.java:167)
        at org.springframework.boot.SpringApplication.deduceMainApplicationClass(SpringApplication.java:283)
        at org.springframework.boot.SpringApplication.<init>(SpringApplication.java:279)
        at org.springframework.boot.SpringApplication.<init>(SpringApplication.java:256)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1307)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1296)
        at com.example.commandlinerunner.CommandlinerunnerApplication.main(CommandlinerunnerApplication.java:10)

Start in SpringApplication.java around deduceMainApplicationClass and findMainClass, and review the change in pull request 31828. Reproduce or inspect the native image failure involving StackWalker.StackFrame.getMethodType; done means main application class deduction no longer invokes the unsupported operation in a native image deployment.