Merge branch 'md/list-objects-filter-memfix' into maint

The filter_data used in the list-objects-filter (which manages a lazily sparse clone repository) did not use the dynamic array API correctly---'nr' is supposed to point at one past the last element of the array in use. This has been corrected. * md/list-objects-filter-memfix: list-objects-filter: correct usage of ALLOC_GROW