Enforce minimum version due to lint check

Author: Jake-Shadle

Cargo.lock

@@ -35,7 +35,9 @@ skip-toolchain-check = []
 # a proc macro crate to do that through), for the same reasons as the list at
 # the start of `[dependencies]` (avoiding unnecessary rebuilds).
 [build-dependencies]
-syn = { version = "2.0", features = ["extra-traits", "full"] }
+syn = { version = "2.0.50", features = ["extra-traits", "full"] }
+# Avoid https://github.com/rust-lang/rust/issues/113152
+proc-macro2 = ">=1.0.60"
 
 [dependencies]
 # HACK(eddyb) these only exist to unify features across dependency trees,