Spring Update links in reference manual

I update some reference links.

Please check again and tell me if I miss something.

Comment From: sbrannen

@snicoll, I meant to assign this to myself, but I see you've assigned this to yourself in the interim.

I was planning on introducing a variable (attribute, or whatever it's called in Asciidoc) for the Micrometer base link so that we only have to edit/maintain that in one place. Can you please take care of that when merging this issue?

Thanks

Comment From: snicoll

@ngocnhan-tran1996 thank you for making your first contribution to Spring Framework.