If you made a Call Action but now want a Text Action instead, just go to the Action’s Edit Page, tap the Action type in the upper left and select a different type.
Most information such as the call-to-action metadata will transfer to the new Action. If the Action is used in multiple apps, then the type will be updated in all those apps.
A very handy use of this trick is with Group Actions. If you have an action in multiple apps and want more actions in that position in the App, then change the Action to a Group Action and add the Actions in that Group.