Fix javadoc for migration from WebSecurityConfigurerAdapter

[xak2000]

This PR just fixes the code sample in javadocs that errorneously uses WebSecurity parameter in a bean-creation method that doesn't need to have any parameters, as WebSecurity parameter is already provided in WebSecurityCustomizer.customize(WebSecurity web) functional method. Moreover, the sample doesn't even compile because of parameter names collision (the bean factory paramter and lambda parameter).

This fix could also be backported to 5.7.x branch.

[jzheaux]

@xak2000, thanks for the PR. We've recently changed to use forward porting. To that end, will you please rebase this PR to 5.7.x and then upon merging, I'll forward port to 5.8.x, 6.0.x, and main?

[xak2000]

@jzheaux Rebased the PR to 5.7.x and changed target branch to 5.7.x. Should I also rebase on the fresh 5.7.x version or it's good in the current state?

[jzheaux]

Thanks for checking, @xak2000. No need to do a fresh rebase. This is now merged to 5.7.x as well as 5.8.x. In the end, I didn't need to forward-port to 6.0.x or main as I had though, since WebSecurityConfigurerAdapter is removed in those versions.