chore: remove flatten-maven-plugin, Maven 4 resolves ${revision} natively

Author: mariuszs

pom.xml

@@ -197,32 +197,6 @@
 					</includes>
 				</configuration>
 			</plugin>
-			<plugin>
-				<groupId>org.codehaus.mojo</groupId>
-				<artifactId>flatten-maven-plugin</artifactId>
-				<version>1.7.0</version>
-				<configuration>
-					<outputDirectory>${project.build.directory}</outputDirectory>
-					<updatePomFile>true</updatePomFile>
-					<flattenMode>oss</flattenMode>
-				</configuration>
-				<executions>
-					<execution>
-						<id>flatten</id>
-						<phase>prepare-package</phase>
-						<goals>
-							<goal>flatten</goal>
-						</goals>
-					</execution>
-					<execution>
-						<id>flatten-clean</id>
-						<phase>clean</phase>
-						<goals>
-							<goal>clean</goal>
-						</goals>
-					</execution>
-				</executions>
-			</plugin>
 			<plugin>
 				<groupId>org.eluder.coveralls</groupId>
 				<artifactId>coveralls-maven-plugin</artifactId>