Add missing word "the".

Author: ehuss

src/doc/rustc/src/symbol-mangling/v0.md

@@ -5,7 +5,7 @@ It has the following properties:
 
 - It provides an unambiguous string encoding for everything that can end up in a binary's symbol table.
 - It encodes information about generic parameters in a reversible way.
-- The mangled symbols are *decodable* such that demangled form should be easily identifiable as some concrete instance of e.g. a polymorphic function.
+- The mangled symbols are *decodable* such that the demangled form should be easily identifiable as some concrete instance of e.g. a polymorphic function.
 - It has a consistent definition that does not rely on pretty-printing certain language constructs.
 - Symbols can be restricted to only consist of the characters `A-Z`, `a-z`, `0-9`, and `_`.
   This helps ensure that it is platform-independent,