crates/shim-protos/Cargo: relex version requirement for protobuf

Signed-off-by: jiaxiao zhou <[email protected]>

Author: Mossaka

crates/shim-protos/Cargo.toml

@@ -49,7 +49,9 @@ required-features = ["async"]
 
 [dependencies]
 async-trait = { workspace = true, optional = true }
-protobuf = "=3.5"
+# protobuf 3.5 introduces a breaking change: https://github.com/containerd/rust-extensions/issues/295
+# pinning to <3.5.0 until we can update the generated code
+protobuf = ">= 3.0, <3.5.0"
 ttrpc = "0.8.2"
 
 [build-dependencies]