small syntax fix

Author: taodailOryx

docs/relational-databases/in-memory-oltp/a-guide-to-query-processing-for-memory-optimized-tables.md

@@ -219,7 +219,7 @@ Execution of natively compiled stored procedures.
 
  Invocation of a natively compiled stored procedure is described as follows:  
 
-1.  The user issues an **EXEC**_usp_myproc_ statement.  
+1.  The user issues an **EXEC** _usp_myproc_ statement.  
 
 2.  The parser extracts the name and stored procedure parameters.