fix code block

C-type-refactoring-guidelines.md

@@ -38,7 +38,7 @@ We should try to keep structs small, if possible. To that end:
 #### External interfaces
 - For functions interfacing other processes over a transport/serialization mechanism, fixed-width types are preferred. For example, in `msgpack_rpc.h`:
 
-  ```c
+```c
 bool msgpack_rpc_integer_result(uint32_t result,
                                 msgpack_object *req,
                                 msgpack_packer *res);
@@ -46,7 +46,7 @@ bool msgpack_rpc_integer_result(uint32_t result,
 
 - For functions part of a public API, native types are preferred. For example, in a hypothetical `libneovim.h`:
 
-  ```c
+```c
 int neovim_get_current_buffer(void);
 ```
 
@@ -65,4 +65,4 @@ In loops, we have a *counter* variable and a *limit* expression (*condition* bei
 - If resulting type of *counter* and *limit* is unsigned:
     * Check *limit* expression  for frontier values (e.g., when size is zero).
     * Avoid *condition* using substractions (unless guarded so that it can be proved for result to always be positive). Prefer equivalent condition using additions on the other side.
-- As an optimization, you could use plain `int` instead of `ssize`, or `unsigned int` instead of `size_t`, but only if you are sure that those types will be enough always. Please try not to impose arbitrary/unneeded limits.
+- As an optimization, you could use plain `int` instead of `ssize`, or `unsigned int` instead of `size_t`, but only if you are sure that those types will be enough always. Please try not to impose arbitrary/unneeded limits.