[comm-lib] Add missing feature dependency to Cargo.toml

Summary: Noticed that this was missing and compilation failed for services with enabled `blob-client` feature, but disabled `http` feature.

Test Plan: cargo build -p comm-lib --all-features

Reviewers: varun, will, kamil

Reviewed By: kamil

Subscribers: ashoat, tomek

Differential Revision: https://phab.comm.dev/D13649

shared/comm-lib/Cargo.toml

@@ -11,6 +11,7 @@ blob-client = [
   "dep:reqwest",
   "dep:futures-core",
   "dep:futures-util",
+  "dep:tokio-stream",
 ]
 http = [
   "dep:actix-cors",