feat: add method for "run a scheduled pipeline immediately"

src/main/java/org/gitlab4j/api/PipelineApi.java

@@ -546,6 +546,19 @@ public PipelineSchedule takeOwnershipPipelineSchedule(Object projectIdOrPath, Lo
         return (response.readEntity(PipelineSchedule.class));
     }
 
+    /**
+     * Trigger a new scheduled pipeline, which runs immediately.
+     *
+     * <pre><code>POST /projects/:id/pipeline_schedules/:pipeline_schedule_id/play</code></pre>
+     *
+     * @param projectIdOrPath projectIdOrPath the project in the form of an Long(ID), String(path), or Project instance, required
+     * @param pipelineScheduleId the pipelineSchedule instance id which should run immediately
+     * @throws GitLabApiException if any exception occurs during execution
+     */
+    public void playPipelineSchedule(Object projectIdOrPath, Long pipelineScheduleId) throws GitLabApiException {
+        post(Response.Status.CREATED, "", "projects", getProjectIdOrPath(projectIdOrPath),  "pipeline_schedules", pipelineScheduleId, "play");
+    }
+
     /**
      * Create a pipeline schedule variable.
      *

src/test/java/org/gitlab4j/api/TestPipelineApi.java

@@ -146,6 +146,26 @@ public void testCreateAndUpdateProjectPipeLineSchedule() throws GitLabApiExcepti
         assertTrue(scheduleDecriptions.contains(newScheduleDescription));
     }
 
+    @Test
+    void testPlayScheduledPipeline() throws GitLabApiException {
+        assertNotNull(testProject);
+
+        String scheduleDescription = SCHEDULE_DESCRIPTION + " - test playScheduledPipeline()";
+        PipelineSchedule newPipelineSchedule = new PipelineSchedule();
+        newPipelineSchedule.setDescription(scheduleDescription);
+        newPipelineSchedule.setCron("3 4 * * *");
+        newPipelineSchedule.setRef("master");
+        PipelineSchedule createdPipelineSchedule = gitLabApi.getPipelineApi().createPipelineSchedule(testProject, newPipelineSchedule);
+        assertNotNull(createdPipelineSchedule);
+
+        // Make sure the created schedule is present before playing
+        List<PipelineSchedule> pipelineSchedules = gitLabApi.getPipelineApi().getPipelineSchedules(testProject);
+        assertNotNull(pipelineSchedules);
+        assertTrue(pipelineSchedules.stream().map(PipelineSchedule::getDescription).collect(toList()).contains(scheduleDescription));
+
+        gitLabApi.getPipelineApi().playPipelineSchedule(testProject, createdPipelineSchedule.getId());
+    }
+
     @Test
     public void testDeleteProjectPipeLineSchedule() throws GitLabApiException {