add ZArray to ZGroup arrays dict in zcreate

[visr]

I created a group with a few arrays like so:

using Zarr

nrow = 1300
ncol = 1200
cellsize = 250.0
zpath = "data/chloride.zarr"

"Prepare an empty Zarr group with populated axes"
function prepare_zarr(path, nrow, ncol, cellsize)
    # only use compression on the data, not on the axes
    compressor = Zarr.BloscCompressor()
    # remove possible old zarr
    rm(path, force = true, recursive = true)
    store = DirectoryStore(path)
    group = zgroup(store)
    zchloride = Zarr.zcreate(
        Float64,
        group,
        "chloride",
        nrow,
        ncol;
        chunks = (100, 100),
        compressor = compressor,
    )
    zx = Zarr.zcreate(Float64, group, "x", ncol; compressor = Zarr.NoCompressor())
    zy = Zarr.zcreate(Float64, group, "y", nrow; compressor = Zarr.NoCompressor())
    zx[:] = range(cellsize / 2, step = cellsize, length = ncol)
    zy[:] = range(625000 - cellsize / 2, step = -250.0, length = nrow)
    return group
end

group = prepare_zarr(zpath, nrow, ncol, cellsize)

But was surprised to find that I could not retrieve the arrays from the group with group["chloride"]. This was because g.arrays (used by getindex) was empty. This commit populates g.arrays during zcreate.

[meggart]

Of course, thanks for the fix. I will merge although this fails on nightly, let's find out later what has happened. Would you mind to increase the patch version number so that we can make a release with this fix, it might affect other users as well.

[visr]

Ok, thanks, I bumped the patch as well.