Fix javadoc generation

spring-boot-project/spring-boot-docs/pom.xml

@@ -236,11 +236,21 @@
 			<artifactId>micrometer-registry-jmx</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-new-relic</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>io.micrometer</groupId>
 			<artifactId>micrometer-registry-prometheus</artifactId>
 			<optional>true</optional>
 		</dependency>
+		<dependency>
+			<groupId>io.micrometer</groupId>
+			<artifactId>micrometer-registry-signalfx</artifactId>
+			<optional>true</optional>
+		</dependency>
 		<dependency>
 			<groupId>io.micrometer</groupId>
 			<artifactId>micrometer-registry-statsd</artifactId>