Remove spring.factories from oauth2login-webflux sample

Fixes gh-5723

samples/boot/oauth2login-webflux/src/main/resources/META-INF/spring.factories

@@ -1,3 +0,0 @@
-# Auto Configure
-org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
-org.springframework.boot.autoconfigure.security.oauth2.client.ReactiveOAuth2ClientAutoConfiguration