Fix grammar

Co-authored-by: Kseniia Sumarokova <54203879+kssenii@users.noreply.github.com>

src/Interpreters/Cache/FileCache.cpp

@@ -586,7 +586,7 @@ bool FileCache::tryReserve(FileSegment & file_segment, size_t size)
         ~EvictionCandidates()
         {
             /// If failed to reserve space, we don't delete the candidates but drop the flag instead
-            /// so the segments can used again
+            /// so the segments can be used again
             for (const auto & candidate : candidates)
                 candidate->removal_candidate = false;
         }