Cannot retrieve gzipped tables from CDS using astropy.table #6549

At CDS (some? all?) ASCII tables are now gzipped.

This causes problems with astropy. For example

from astropy.table import Table

t = Table.read("ftp://cdsarc.u-strasbg.fr/pub/cats/J/MNRAS/445/2677/table1.dat.gz",
                readme="ftp://cdsarc.u-strasbg.fr/pub/cats/J/MNRAS/445/2677/ReadMe",
                format="ascii.cds")
print(t)

gives the error
astropy.io.ascii.core.InconsistentTableError: Can't find table table1.dat.gz in ftp://cdsarc.u-strasbg.fr/pub/cats/J/MNRAS/445/2677/ReadMe

because the ReadMe
ReadMe.txt
says
"Byte-by-byte Description of file: table1.dat"
and not
"Byte-by-byte Description of file: table1.dat.gz"