How to remove additional vertical line from dock created by Automator app

Can you help me by telling how to remove vertical line from dock created by Automator App. As you told that we can create it by following this process but i want to know how to remove it.

Using Automator to Create an App:

• Open Automator.
• Select "New Document" in the lower left.
• Choose a type for your document - Application.
• Find "Launch Application" from the list, and drag it into - the workspace on the right.
• Select the Finder app.
  • To do this, you have to go down to "New Variable." It will tell you to select the path. Click the dropdown, and go down to "Other." Do a search for "Finder.app" and select it.
  • Then click "Done."
• Click "Run" in the upper right hand corner, just to make sure it launches the Finder.
• Go to File > Export...
  • Name the file and choose a location for it. I picked my Applications folder.
  • Click Save.
• Repeat steps 7 & 8 for as many lines you want, changing the name each time. I kept the names numerical for ease of use. line1.app, line2.app, etc.

The Automator workflow isn't what caused the vertical lines, as there is nothing in the workflow capable of doing that. There is a new feature, since macOS Mojave, in System Preferences > Dock which added an additional vertical line, [√] Show recent applications in Dock. Uncheck it and the vertical line on the left will go away.