feat(core): new sleep task

close #4879 
Co-authored-by: YannC <ycoornaert@kestra.io>

core/src/main/java/io/kestra/plugin/core/flow/Sleep.java

@@ -0,0 +1,57 @@
+package io.kestra.plugin.core.flow;
+
+import io.kestra.core.models.annotations.Example;
+import io.kestra.core.models.annotations.Plugin;
+import io.kestra.core.models.annotations.PluginProperty;
+import io.kestra.core.models.tasks.RunnableTask;
+import io.kestra.core.models.tasks.Task;
+import io.kestra.core.models.tasks.VoidOutput;
+import io.kestra.core.runners.RunContext;
+import io.swagger.v3.oas.annotations.media.Schema;
+import jakarta.validation.constraints.NotNull;
+import lombok.EqualsAndHashCode;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.ToString;
+import lombok.experimental.SuperBuilder;
+
+import java.time.Duration;
+import java.util.concurrent.TimeUnit;
+
+@SuperBuilder
+@ToString
+@EqualsAndHashCode
+@Getter
+@NoArgsConstructor
+@Schema(
+    title = "A task that sleep for a specified duration before proceeding."
+)
+@Plugin(
+    examples = {
+        @Example(
+            code = """
+                    id: sleep
+                    type: io.kestra.plugin.core.flow.Sleep
+                    duration: "PT5S"
+                """
+        )
+    }
+)
+public class Sleep extends Task implements RunnableTask<VoidOutput> {
+    @Schema(
+        title = "Duration to sleep",
+        description = "The time duration in ISO-8601 format (e.g., `PT5S` for 5 seconds)."
+    )
+    @PluginProperty
+    @NotNull
+    private Duration duration;
+
+    public VoidOutput run(RunContext runContext) throws Exception {
+        runContext.logger().info("Waiting for {}", duration);
+
+        // Wait for the specified duration
+        TimeUnit.MILLISECONDS.sleep(duration.toMillis());
+
+        return null;
+    }
+}

core/src/test/java/io/kestra/plugin/core/flow/SleepTest.java

@@ -0,0 +1,23 @@
+package io.kestra.plugin.core.flow;
+
+import io.kestra.core.models.executions.Execution;
+import io.kestra.core.models.flows.State;
+import io.kestra.core.queues.QueueException;
+import io.kestra.core.runners.AbstractMemoryRunnerTest;
+import org.junit.jupiter.api.Test;
+
+import java.util.concurrent.TimeoutException;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+
+public class SleepTest extends AbstractMemoryRunnerTest {
+    @Test
+    void sleepTaskTest() throws TimeoutException, QueueException {
+        Execution execution = runnerUtils.runOne(null, "io.kestra.tests", "sleep-task-flow");
+
+        assertThat(execution.getState().getCurrent(), is(State.Type.SUCCESS));
+    }
+
+
+}

core/src/test/resources/flows/valids/sleep-task-flow.yaml

@@ -0,0 +1,9 @@
+id: sleep-task-flow
+namespace: io.kestra.tests
+
+tasks:
+  - id: sleep
+    type: io.kestra.plugin.core.flow.Sleep
+    duration: PT2S
+
+