Update service metadata for updated Blobs only
Update service metadata for updated Blobs only

Follow-up to #40013.

Newly created `Blob`s may not be uploaded yet, so do not try to update
their service metadata.
yawboakye/rails,starknx/rails,esparta/rails,eileencodes/rails,Vasfed/rails,Stellenticket/rails,schuetzm/rails,tjschuck/rails,Erol/rails,MSP-Greg/rails,MSP-Greg/rails,Stellenticket/rails,bogdanvlviv/rails,EmmaB/rails-1,tgxworld/rails,yawboakye/rails,schuetzm/rails,tgxworld/rails,tjschuck/rails,bogdanvlviv/rails,Vasfed/rails,esparta/rails,yalab/rails,bogdanvlviv/rails,BlakeWilliams/rails,Stellenticket/rails,BlakeWilliams/rails,lcreid/rails,repinel/rails,EmmaB/rails-1,rafaelfranca/omg-rails,kddeisz/rails,esparta/rails,vipulnsward/rails,Vasfed/rails,Envek/rails,repinel/rails,Vasfed/rails,joonyou/rails,Edouard-chin/rails,Envek/rails,kmcphillips/rails,yalab/rails,yahonda/rails,esparta/rails,MSP-Greg/rails,kddeisz/rails,tjschuck/rails,schuetzm/rails,starknx/rails,Erol/rails,rails/rails,repinel/rails,rails/rails,tgxworld/rails,yahonda/rails,BlakeWilliams/rails,joonyou/rails,betesh/rails,Edouard-chin/rails,Erol/rails,joonyou/rails,kddeisz/rails,vipulnsward/rails,eileencodes/rails,kddeisz/rails,yalab/rails,Envek/rails,betesh/rails,rails/rails,yalab/rails,tjschuck/rails,BlakeWilliams/rails,kmcphillips/rails,tgxworld/rails,georgeclaghorn/rails,georgeclaghorn/rails,rails/rails,rafaelfranca/omg-rails,starknx/rails,Stellenticket/rails,yahonda/rails,betesh/rails,schuetzm/rails,EmmaB/rails-1,betesh/rails,eileencodes/rails,repinel/rails,Envek/rails,lcreid/rails,joonyou/rails,rafaelfranca/omg-rails,lcreid/rails,MSP-Greg/rails,bogdanvlviv/rails,kmcphillips/rails,eileencodes/rails,yawboakye/rails,Edouard-chin/rails,lcreid/rails,yawboakye/rails,vipulnsward/rails,Erol/rails,kmcphillips/rails,georgeclaghorn/rails,vipulnsward/rails,yahonda/rails,georgeclaghorn/rails,Edouard-chin/rails