Make clear that start/end are inclusive
Make clear that start/end are inclusive

Fixes: https://github.com/prometheus/prometheus/issues/9100

Signed-off-by: Richard Hartmann <dbc5c9b9cbc722d5250b7cedc577ded204477545@richih.org>

alileza/prometheus,alileza/prometheus,alileza/prometheus,alileza/prometheus,prometheus/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,prometheus/prometheus,prometheus/prometheus,alileza/prometheus,prometheus/prometheus,keegancsmith/prometheus,prometheus/prometheus,keegancsmith/prometheus