Remove repeated words (#1252)

doc/ondemand.md

@@ -105,7 +105,7 @@ or indexing (`object["key"]`). In some cases, the values are even deserialized d
 maps.
 
 The DOM approach is conceptually simple and "programmer friendly". Using the
-DOM tree is often easy enough that many users use the DOM as-is instead of creating their own
+DOM tree is often easy enough that many users use the DOM as-is instead of creating
 their own custom data structures.
 
 The DOM approach was the only way to parse JSON documents up to version 0.6 of the simdjson library.
@@ -626,4 +626,4 @@ the `CMAKE_CXX_FLAGS` variable:
 ```
 cmake  -DCMAKE_CXX_FLAGS="-march=haswell" -B build_haswell
 cmake --build build_haswell
-```
+```