Docs: fix long-traces.md
Docs: fix long-traces.md

Missing alias in front of protoc

Change-Id: I92ce6d7602f8976afb209a77d8df3fd9811c7f5f
google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto