Feature request

Feature description
A command to toggle keepinv for players who have the essentials.keepinv perm.

How the feature is useful
It allows players who have the essentials.keepinv perm to remove curse of binding items.

You can now use the keepinv policy config options introduced in EssentialsX 2.18.0 (#3328) to allow players to remove Curse of Binding and Curse of Vanishing items. Quote from 2.18.0 changelog:

You can now configure how the essentials.keepinv permission behaves when players die while holding items with the Curse of Binding or Curse of Vanishing:

# How should essentials handle players with the essentials.keepinv permission who have items with
# curse of vanishing when they die?
# You can set this to "keep" (to keep the item), "drop" (to drop the item), or "delete" (to delete the item).
# Defaults to "keep"
vanishing-items-policy: keep

# How should essentials handle players with the essentials.keepinv permission who have items with
# curse of binding when they die?
# You can set this to "keep" (to keep the item), "drop" (to drop the item), or "delete" (to delete the item).
# Defaults to "keep"
binding-items-policy: keep