Add toggle action to award emoji update mutation

What does this MR do and why?

As discussed in this comment, we need to add the toggle action to our award emoji update mutation, in order to be able to consume it when we add an /award quick action for work items (#412275 (closed))

Screenshots or screen recordings

Screen_Recording_2023-09-11_at_22.02.15

How to set up and validate locally

1. Using the rails console, create a work item:

user = User.first
project = Project.first
WorkItem.create!(project: project, author: user, title: 'Test Work Item Emoji Award')

2. Visit GDK_URL/-/graphql-explorer and enter the following query:

mutation toggleWorkItemEmojiAward {
  workItemUpdate(input: {id: "gid://gitlab/WorkItem/$WORK_ITEM_ID", awardEmojiWidget: { action: TOGGLE, name: "rocket"}}) {
    workItem {
      id
      widgets{
        ... on WorkItemWidgetAwardEmoji {
          upvotes
          downvotes
          awardEmoji {
            edges {
              node {
                name
                user {
                  id
                }
              }
            }
          }
        }
      }
    }
    errors
  }
}

3. Visit the work item and verify that the 🚀 emoji award is toggled on/off when the graphql query is executed repeatedly

MR acceptance checklist

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