add workflow management (#1493)

* add workflow management

* update

* Update 3.workflow-management.md

* Update 3.workflow-management.md

docs-2.0/nebula-explorer/workflow/3.workflow-management.md

@@ -0,0 +1,20 @@
+# Workflow management
+
+This topic describes how to manage workflows, including view, modify, rename, clone, delete, and compare workflows.
+
+## Steps
+
+1. At the top of the Explorer page, click **Workflow**.
+
+2. In the **Workflows** tab, users can view all saved workflows. The list displays `Workflow name`, `Created time`, `Update time`, and `Algorithm`.
+
+  - At the top of the list page, click **Comparison** and select two workflows or different historical versions of the same workflow for code comparison.
+
+  - At the top of the list page, users can search the workflow by keywords in the search box.
+
+  - In the **Operation** column of the list page, users an perform the following operations:
+
+    - **Run**: Instantiate the workflow directly as a job and execute the job.
+    - **Open**: Open a workflow to view and modify the workflow. After modifying the workflow, click ![save](https://docs-cdn.nebula-graph.com.cn/figures/workflow-save-220623.png) to save the modification or click ![save](https://docs-cdn.nebula-graph.com.cn/figures/workflow-saveAs-220623.png) to save the workflow as a new workflow.
+    - **View jobs**: Jump to the job list to view all the jobs instantiated by this workflow.
+    - ![save](https://docs-cdn.nebula-graph.com.cn/figures/workflow-more-220623.png): Users can view the workflow code, rename the workflow, clone the workflow, and delete the workflow.