assertion() when opening a Zarr dataset with "dtype":"|u1"

[rouault]

netcdf git at 84f0696, Ubuntu 20.04
on the attached zarr dataset byte.zarr.zip (after unzipping it),

$ gdb --args ncdump/ncdump "file:///tmp/byte.zarr#mode=zarr,file"
(gdb) r
Program received signal SIGABRT, Aborted.
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50	../sysdeps/unix/sysv/linux/raise.c: Aucun fichier ou dossier de ce type.
(gdb) bt
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007ffff7bf3859 in __GI_abort () at abort.c:79
#2  0x00007ffff7bf3729 in __assert_fail_base (fmt=0x7ffff7d89588 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x7ffff7f831f0 "type && type->format_type_info != NULL", 
    file=0x7ffff7f83128 "/home/even/netcdf-c/libnczarr/zclose.c", line=225, function=<optimized out>) at assert.c:92
#3  0x00007ffff7c04f36 in __GI___assert_fail (assertion=0x7ffff7f831f0 "type && type->format_type_info != NULL", file=0x7ffff7f83128 "/home/even/netcdf-c/libnczarr/zclose.c", line=225, 
    function=0x7ffff7f83258 <__PRETTY_FUNCTION__.9091> "zclose_type") at assert.c:101
#4  0x00007ffff7effedc in zclose_type (type=0x0) at /home/even/netcdf-c/libnczarr/zclose.c:225
#5  0x00007ffff7effd11 in zclose_vars (grp=0x5555555c8990) at /home/even/netcdf-c/libnczarr/zclose.c:172
#6  0x00007ffff7effa16 in zclose_group (grp=0x5555555c8990) at /home/even/netcdf-c/libnczarr/zclose.c:91
#7  0x00007ffff7eff891 in ncz_close_file (file=0x5555555c88c0, abort=1) at /home/even/netcdf-c/libnczarr/zclose.c:44
#8  0x00007ffff7f07b6f in ncz_open_file (path=0x5555555c80f0 "file:///tmp/byte.zarr#mode=zarr,file,nczarr", mode=4096, controls=0x5555555c87d0, ncid=65536) at /home/even/netcdf-c/libnczarr/zopen.c:127
#9  0x00007ffff7f07c73 in NCZ_open (path=0x5555555c80f0 "file:///tmp/byte.zarr#mode=zarr,file,nczarr", mode=4096, basepe=0, chunksizehintp=0x0, parameters=0x0, dispatch=0x7ffff7fb08e0 <NCZ_dispatcher>, 
    ncid=65536) at /home/even/netcdf-c/libnczarr/zopen.c:183
#10 0x00007ffff7e27ee4 in NC_open (path0=0x55555558c940 "file:///tmp/byte.zarr#mode=zarr,file", omode=4096, basepe=0, chunksizehintp=0x0, useparallel=0, parameters=0x0, ncidp=0x7fffffffce04)
    at /home/even/netcdf-c/libdispatch/dfile.c:2128
#11 0x00007ffff7e26c07 in nc_open (path=0x55555558c940 "file:///tmp/byte.zarr#mode=zarr,file", omode=0, ncidp=0x7fffffffce04) at /home/even/netcdf-c/libdispatch/dfile.c:657
#12 0x000055555555e141 in main (argc=1, argv=0x7fffffffdf50) at /home/even/netcdf-c/ncdump/ncdump.c:2423

This is due to "dtype":"|u1", which is valid. Changing it to "<u1" works around the issue