Fixed robots.txt according to Google tester
Fixed robots.txt according to Google tester

Signed-off-by: Bryan Jacquot <dd38254abf44cedd01d2ae768f52d5b8eb744c9b@hpe.com>

grommet/grommet-docs,grommet/grommet-docs,karatechops/grommet-docs,karatechops/grommet-docs