Remove WebFluxExtensionInitializer and factory

Delete WebFluxExtensionInitializer and its unit test, and remove its ApplicationContextInitializer registration from microsphere-spring-webflux/src/main/resources/META-INF/spring.factories. The SpringWebFluxHelper entry is kept. Removed files: src/main/java/io/microsphere/spring/webflux/annotation/WebFluxExtensionInitializer.java and src/test/java/io/microsphere/spring/webflux/annotation/WebFluxExtensionInitializerTest.java; modified: META-INF/spring.factories.

Author: mercyblitz

microsphere-spring-webflux/src/main/java/io/microsphere/spring/webflux/annotation/WebFluxExtensionInitializer.java

@@ -1,7 +1,3 @@
 # SpringWebHelper
 io.microsphere.spring.web.util.SpringWebHelper=\
-io.microsphere.spring.webflux.util.SpringWebFluxHelper
-
-# ApplicationContextInitializer
-org.springframework.context.ApplicationContextInitializer=\
-io.microsphere.spring.webflux.annotation.WebFluxExtensionInitializer
+io.microsphere.spring.webflux.util.SpringWebFluxHelper