feat: reduce LOADER_DELAY to 600 (#244)

As discussed in the web sync and in https://docs.google.com/document/d/1TPTH33vOVXqhKgVEeohnZh1sZA02M_hfZVx0YBvX5QI/edit

Author: Loïc Guychard

src/hoverifier.ts

@@ -326,7 +326,7 @@ const internalToExternalState = <C extends object, D, A>(
 })
 
 /** The time in ms after which to show a loader if the result has not returned yet */
-export const LOADER_DELAY = 1200
+export const LOADER_DELAY = 600
 
 /** The time in ms after the mouse has stopped moving in which to show the tooltip */
 export const TOOLTIP_DISPLAY_DELAY = 100