replace keyword details with note (#7061)

Author: Mukulyadav2004

man/last.Rd

@@ -18,8 +18,8 @@ of \code{xts::first} is deployed. }
 \item{\dots}{ Not applicable for \code{data.table} first/last. Any arguments here
 are passed through to \code{xts}'s first/last. }
 }
-\details{
-Note: For zero-length vectors, \code{first(x)} and \code{last(x)} mimic \code{head(x, 1)} and \code{tail(x, 1)} by returning an empty vector instead of \code{NA}. However, unlike \code{head()}/\code{tail()} and base R subsetting (e.g., \code{x[1]}), they do not preserve attributes like names.
+\note{
+For zero-length vectors, \code{first(x)} and \code{last(x)} mimic \code{head(x, 1)} and \code{tail(x, 1)} by returning an empty vector instead of \code{NA}. However, unlike \code{head()}/\code{tail()} and base R subsetting (e.g., \code{x[1]}), they do not preserve attributes like names.
 }
 \value{
 If no other arguments are supplied it depends on the type of \code{x}. The first/last item