improve docs slightly

Author: Byron

gix-refspec/src/match_group/util.rs

@@ -13,7 +13,7 @@ pub struct Matcher<'a> {
 
 impl<'a> Matcher<'a> {
     /// Match `item` against this spec and return `(true, Some<rhs>)` to gain the other side of the match as configured, or `(true, None)`
-    /// if there was no `rhs`.
+    /// if there was no `rhs` but the `item` matched. Lastly, return `(false, None)` if `item` didn't match at all.
     ///
     /// This may involve resolving a glob with an allocation, as the destination is built using the matching portion of a glob.
     pub fn matches_lhs(&self, item: Item<'_>) -> (bool, Option<Cow<'a, BStr>>) {