tid: remove set children as parent tid is always set before
tid: remove set children as parent tid is always set before

Since graph even are synchronous and the metadata attributes
needed to set the TID it appears that is useless to set children
TID, they will be set by OnEdgeAdded.

Change-Id: I19003aa92b5be998f7dc7a181f9c6b1e51de5cf4
Reviewed-on: https://softwarefactory-project.io/r/7565
Reviewed-by: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>
Tested-by: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>
Workflow: Sylvain Baubeau <b0a7dc08a3f38d713e107103b0a85b0badc14b84@redhat.com>
Tested-by: Jenkins CI <d95b56ce41a2e1ac4cecdd398defd7414407cc08@softwarefactory-project.io>

lebauce/skydive,skydive-project/skydive,safchain/skydive,lebauce/skydive,skydive-project/skydive,safchain/skydive,safchain/skydive,lebauce/skydive,skydive-project/skydive,safchain/skydive,lebauce/skydive,skydive-project/skydive,safchain/skydive,lebauce/skydive,safchain/skydive,safchain/skydive,lebauce/skydive,lebauce/skydive,lebauce/skydive,safchain/skydive,skydive-project/skydive,skydive-project/skydive,skydive-project/skydive