Fix //rust/release_crates:cargo_test by making 0.x and 4.x synonymous

rust/internal.rs

diff --git a/rust/internal.rs b/rust/internal.rs
index b462d23..f787927 100644
--- a/rust/internal.rs
+++ b/rust/internal.rs
@@ -151,9 +151,10 @@
     assert!(
         are_versions_compatible(gencode_version, runtime_version),
         concat!(
-            "Gencode version is not compatible with runtime version (runtime is ",
+            "Gencode version (see callsite) is not compatible with runtime ",
+            "version (runtime is ",
             env!("CARGO_PKG_VERSION"),
-            ", gencode version is at the callsite)"
+            ")"
         ),
     );
 }