Data delivery: Fix geo_region definition

[agstephens]

Harmonise definition of geo_region:

LS2 and LS3 maps and csv are working for regions.
But not LS1. The data is slightly different.
In LS2 and LS3:

```char geo_region(region, string24) ;
    geo_region:units = "1" ;
    geo_region:standard_name = "region" ;
    geo_region:long_name = "Administrative Region" ;```

And in LS1:

```char geo_region(region, string26) ;
    geo_region:units = "1" ;
    geo_region:long_name = "Administrative Region" ;```