[Services] Update blob to reference new directory
Summary:
Update blob references to protobuf directory
https://linear.app/comm/issue/ENG-1231
Depends on D4996
Test Plan:
nix develop cd services/blob rm -rf build && mkdir build && cd build && cmake .. && make -j
Reviewers: atul, abosh, varun, max, karol, tomek
Reviewed By: atul, max, karol, tomek
Subscribers: ashoat, tomek
Differential Revision: https://phab.comm.dev/D4998