Upgrade Protobuf Maven Plugin to 3.4.2

 See gh-1838

Signed-off-by: Dave Syer <david.syer@broadcom.com>

Author: dsyer

start-site/src/main/java/io/spring/start/site/extension/dependency/springgrpc/GrpcMavenBuildCustomizer.java

@@ -29,7 +29,7 @@
  */
 class GrpcMavenBuildCustomizer implements BuildCustomizer<MavenBuild> {
 
-	private static final String PROTOBUF_PLUGIN_VERSION = "3.3.1";
+	private static final String PROTOBUF_PLUGIN_VERSION = "3.4.2";
 
 	private final String protobufJavaVersion;
 
@@ -58,7 +58,6 @@ private void addProtobufPlugin(MavenPluginContainer plugins, VersionProperty pro
 		plugins.add("io.github.ascopes", "protobuf-maven-plugin", (plugin) -> {
 			plugin.version(PROTOBUF_PLUGIN_VERSION);
 			plugin.configuration((configuration) -> {
-				configuration.add("sourceDirectories", (builder) -> builder.add("sourceDirectory", "src/main/proto"));
 				configuration.add("protocVersion", "${%s}".formatted(protobufJava.toStandardFormat()));
 				configuration.add("binaryMavenPlugins", (builder) -> {
 					builder.add("binaryMavenPlugin", (binary) -> {
@@ -69,10 +68,7 @@ private void addProtobufPlugin(MavenPluginContainer plugins, VersionProperty pro
 					});
 				});
 			});
-			plugin.execution("generate", (execution) -> {
-				execution.m2e("execute onConfiguration,onIncremental");
-				execution.goal("generate");
-			});
+			plugin.execution("generate", (execution) -> execution.goal("generate"));
 		});
 	}
 

start-site/src/test/java/io/spring/start/site/extension/dependency/springgrpc/SpringGrpcProjectGenerationConfigurationTests.java

@@ -123,11 +123,8 @@ void shouldAddProtobufPluginForMaven() {
 					<plugin>
 						<groupId>io.github.ascopes</groupId>
 						<artifactId>protobuf-maven-plugin</artifactId>
-						<version>3.3.1</version>
+						<version>3.4.2</version>
 						<configuration>
-							<sourceDirectories>
-								<sourceDirectory>src/main/proto</sourceDirectory>
-							</sourceDirectories>
 							<protocVersion>${protobuf-java.version}</protocVersion>
 							<binaryMavenPlugins>
 								<binaryMavenPlugin>
@@ -140,7 +137,6 @@ void shouldAddProtobufPluginForMaven() {
 						</configuration>
 						<executions>
 							<execution>
-								<?m2e execute onConfiguration,onIncremental?>
 								<id>generate</id>
 								<goals>
 									<goal>generate</goal>