Remove dependency on javax.annotation

This commit removes the directy dependency that was required
by the protoc compiler for our samples. The Maven and Gradle
now support an option to use an internal annotation which then
allows us to remove the deprecated javax.annotation dependency.

Background here: https://github.com/grpc/grpc-java/pull/10927

samples/grpc-server/build.gradle

@@ -52,7 +52,9 @@ protobuf {
     }
     generateProtoTasks {
         all()*.plugins {
-            grpc {}
-        }
+            grpc {
+				option 'jakarta_omit'
+			}
+		}
     }
 }

samples/grpc-server/pom.xml

@@ -120,14 +120,6 @@
 				<groupId>org.xolstice.maven.plugins</groupId>
 				<artifactId>protobuf-maven-plugin</artifactId>
 				<version>0.6.1</version>
-				<executions>
-					<execution>
-						<goals>
-							<goal>compile</goal>
-							<goal>compile-custom</goal>
-						</goals>
-					</execution>
-				</executions>
 				<configuration>
 					<protocArtifact>
 						com.google.protobuf:protoc:${protobuf-java.version}:exe:${os.detected.classifier}</protocArtifact>
@@ -135,6 +127,19 @@
 					<pluginArtifact>
 						io.grpc:protoc-gen-grpc-java:${grpc.version}:exe:${os.detected.classifier}</pluginArtifact>
 				</configuration>
+				<executions>
+					<execution>
+						<configuration>
+							<pluginParameter>
+								jakarta_omit
+							</pluginParameter>
+						</configuration>
+						<goals>
+							<goal>compile</goal>
+							<goal>compile-custom</goal>
+						</goals>
+					</execution>
+				</executions>
 			</plugin>
 		</plugins>
 	</build>

spring-grpc-core/pom.xml

@@ -47,11 +47,6 @@
 			<groupId>io.grpc</groupId>
 			<artifactId>grpc-stub</artifactId>
 		</dependency>
-		<dependency>
-			<groupId>javax.annotation</groupId>
-			<artifactId>javax.annotation-api</artifactId>
-			<version>1.3.2</version>
-		</dependency>
 
 		<dependency>
 			<groupId>org.junit.jupiter</groupId>