docs: fix typo in build_ext command (#687)

Author: khoakhoahihi

docs/source/user/iamaresearcher.rst

@@ -770,7 +770,7 @@ run the following command:
 
 .. code-block:: bash
 
-    python setup.py build_ext —inplace
+    python setup.py build_ext --inplace
 
 This will generate C++ files from Cython files, compile the C++ files, and place the compiled binary files in the necessary folders.