BasicAuthenticationFilter breaks SwitchUserFilter

Describe the bug
When using the SwitchUserFilter with Basic auth, BasicAuthenticationFilter.authenticationIsRequired() fails when switched forcing a re-authentication.

To Reproduce
Enable both basic auth and the SwitchUserFilter, switch to a new user and then make another request.
BasicAuthenticationFilter.authenticationIsRequired() will return true since the current logged in user doesn't match the WWW-Authenticate header

Expected behavior
BasicAuthenticationFilter.authenticationIsRequired() should also check if existingAuth has a GrantedAuthority of ROLE_PREVIOUS_ADMINISTRATOR, and check that username against username

		if (existingAuth instanceof UsernamePasswordAuthenticationToken
				&& !existingAuth.getName().equals(username)) {
			return true;
		}

Start at BasicAuthenticationFilter.authenticationIsRequired() and reproduce the behavior with Basic auth and SwitchUserFilter enabled, switching to another user before making a second request. Done means a switched user does not trigger an unnecessary re-authentication when the existing authentication has ROLE_PREVIOUS_ADMINISTRATOR and matches the requested username.