added vdemeester to codeowners for pipelines operator
added vdemeester to codeowners for pipelines operator

Signed-off-by: Siamak Sadeghianfar <e3c6ec336257e7f6033ef6d0921d851094f0033b@redhat.com>

operator-framework/community-operators,operator-framework/community-operators,operator-framework/community-operators