[#1383] Spring Boot 3 Migration / Step 1 (#1384)

1. PagingAndSortingRepository doesn't extend CrudRepository anymore. For all extending that interface repositories CrudRepository super interface shall be now declared (https://spring.io/blog/2022/02/22/announcing-listcrudrepository-friends-for-spring-data-3-0 -
```
The popular PagingAndSortingRepository used to extend from CrudRepository, but it no longer does. This lets you combine it
with either CrudRepository or ListCrudRepository or a base interface of your own creation. This means you now have to
explicitly extend from a CRUD fragment, even when you already extend from PagingAndSortingRepository.
```
)
2. org.eclipse.hawkbit.autoconfigure.mgmt.ui -> move in hawkbit-ui (to be ready for removal), anyway - it's a better location for ui related configs
3. extends WebMvcConfigurerAdapter -> implements WebMvcConfigurer
4. remove WebSecurityConfigurerAdapter -> https://docs.spring.io/spring-security/reference/5.8/migration/servlet/config.html#_stop_using_websecurityconfigureradapter, https://spring.io/blog/2022/02/21/spring-security-without-the-websecurityconfigureradapter
and add @Order to the bean reg!!
5. Use configurers (the other will be deprecated / removed), e.d:  http.csrf().disable() -> http.csrf(AbstractHttpConfigurer::disable)
6. configure(final AuthenticationManagerBuilder auth) -> put in httpsecurity config - http.getSharedObject(AuthenticationManagerBuilder.class).... (https://www.baeldung.com/spring-security-authentication-provider)
7. configure(final WebSecurity webSecurity) ->
```
@Bean
public WebSecurityCustomizer webSecurityCustomizer() {
    return (web) -> web.ignoring().antMatchers("/documentation/**", "/VAADIN/**", "/*.*", "/docs/**");
}
```
(https://spring.io/blog/2022/02/21/spring-security-without-the-websecurityconfigureradapter)
8. AuthenticationManager authenticationManagerBean() ->
```
@Bean
AuthenticationManager authenticationManager(final AuthenticationConfiguration authenticationConfiguration) throws Exception {
    return authenticationConfiguration.getAuthenticationManager();
}
```
(https://backendstory.com/spring-security-how-to-replace-websecurityconfigureradapter/)
9. WebMvcAutoConfiguration could be removed - it uses deprectated methods, and sets properties that are same by default - hence - not neeeded
(https://github.com/spring-projects/spring-framework/issues/23915#issuecomment-563987147)

Signed-off-by: Marinov Avgustin <Avgustin.Marinov@bosch.com>

CONTRIBUTING.md

@@ -35,8 +35,6 @@ So we kindly ask contributors:
   * use [Guava](https://github.com/google/guava) if feasible
   * use [Apache commons lang](https://commons.apache.org/proper/commons-lang/) if feasible
 
-Note that the guava project for instance often documents where they think that JDK is having a similar functionality (e.g. their thoughts on  [Throwables.propagate](https://github.com/google/guava/wiki/Why-we-deprecated-Throwables.propagate)).
-
 Examples:
 
 * Prefer `Arrays.asList(...)` from JDK over Guava's `Lists.newArrayList(...)`