SpringBoot Fix deprecations in javadocs

Hi,

this PR fixes a couple of deprecations in javadocs following some changes in Spring Framework.

Cheers, Christoph

Comment From: snicoll

Thanks again Christoph.

Comment From: dreis2211

@wilkinsona Why has the commit been reverted?

Comment From: wilkinsona

Oops, sorry. I didn't mean to push that. Thanks for noticing my mistake. I was experimenting to see if I could learn if it was possible to get doclint to fail the build when javadoc references a deprecated method. I've reinstated the changes.