Fix Rendering of SpEL expression example Tabs in method security Documentation

[Meehdi]

Expected Behavior
Render Java and Kotlin tab for the SpEL expression example

Current Behavior
There is a syntax error in the adoc file that prevent the tabs from rendring correctly

Context

In the method security page,in the SpEL expression example the tabs are not rendering correctly.
I want to fix this tabs syntax in the adoc so it renders correctly.

[rwinch]

Thanks for creating this. I'm closing this in favor of your pull request gh-16343