Correctly mark rust code in README.md

jannic · newAM · web-flow · commit 809be1db1c14 · 2023-03-05T17:30:53.000+01:00
Co-authored-by: Alex Martens &lt;alex@thinglab.org&gt;
diff --git a/README.md b/README.md
@@ -14,7 +14,7 @@ This project is developed and maintained by the [Cortex-M team][team].
 
 Starting with Rust 1.68, this crate can be used as a global allocator:
 
-```
+```rust
 #![no_std]
 #![no_main]
 
