events: Add oniro-blueprints-abstract.md
requested to merge pcoval/proposal-incubation-oniro-marketing:sandbox/rzr/events/review/main into main
Relate-to: #9 (closed) Relate-to: https://git.ostc-eu.org/OSTC/planning/events/-/issues/1 Signed-off-by: Philippe Coval philippe.coval@huawei.com