Update grafana.md (#1877)
Update grafana.md (#1877)

Change grafana.org -> grafana.com

Signed-off-by: Martin Schröder <54669547a225ff20cba8b75a4adca540eef25858@oneiros.de>

Co-authored-by: Martin Schröder <d3063a23bfc1791e90709eb3822183996379d96a@users.noreply.github.com>
prometheus/docs,prometheus/docs,prometheus/docs