updated VaadinWebSecurityConfigurerAdapter-implementation for Spring security 5.7+

[MathiasAugstein]

Describe your motivation

Thank you for providing VaadinWebSecurityConfigurerAdapter, so the Spring settings do not need to be copy-pasted manually anymore. However with Spring Security 5.7 the WebSecurityConfigurerAdapter got deprecated, and should be replaced by a SecurityFilterChain implementation. It would be nice if Vaadin could help with this migration by providing a default implementation.

Describe the solution you'd like

• creation of another class like VaadinWebSecurityConfigurerAdapter following the new Spring Security standard
• adding deprecated-note to VaadinWebSecurityConfigurerAdapter with a link to the new implementation
• nice-to-have: migration guide for people who used VaadinWebSecurityConfigurerAdapter with custom changes

[knoobie]

This was already done in #14303 and should be available in 23.2.0 in September.

[MathiasAugstein]

Thanks, seems I was not searching good enough through your Github Issues.