Update Project Lombok version to 1.16.20

Update Project Lombok version to 1.16.20 (from 1.16.18) and specify this
version in runelite-parent instead of having it specified all around the
maven projects.

Signed-off-by: Tomas Slusny <slusnucky@gmail.com>

pom.xml

@@ -38,6 +38,7 @@
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 		<java.version>1.8</java.version>
+		<lombok.version>1.16.20</lombok.version>
 
 		<maven.javadoc.skip>true</maven.javadoc.skip>
 		<checkstyle.skip>true</checkstyle.skip>
@@ -61,7 +62,7 @@
 		<developerConnection>scm:git:git@github.com:runelite/runelite</developerConnection>
 		<tag>HEAD</tag>
 	</scm>
-	
+
 	<developers>
 		<developer>
 			<id>Adam-</id>
@@ -129,6 +130,12 @@
 				<artifactId>guava</artifactId>
 				<version>23.2-jre</version>
 			</dependency>
+			<dependency>
+				<groupId>org.projectlombok</groupId>
+				<artifactId>lombok</artifactId>
+				<version>${lombok.version}</version>
+				<scope>provided</scope>
+			</dependency>
 		</dependencies>
 	</dependencyManagement>