Allow static import for org.springframework.security.test.web.reactive.server.SecurityMockServerConfigurers.*

It would be nice to allow imports for `org.springframework.security.test.web.reactive.server.SecurityMockServerConfigurers.*`

```java
		webTestClient.mutateWith(csrf())
```

vs

```java
		webTestClient.mutateWith(SecurityMockServerConfigurers.csrf())
```