Update virtualenvs.rst

Author: Sidra-Maryam

docs/dev/virtualenvs.rst

@@ -360,7 +360,7 @@ To install (make sure **virtualenv** is already installed):
 In Windows, the default path for WORKON_HOME is %USERPROFILE%\\Envs
 
 Basic Usage
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+-----------
 
 1. Create a virtual environment:
 
@@ -404,7 +404,7 @@ can quickly switch between environments.
    $ rmvirtualenv venv
 
 Other useful commands
-~~~~~~~~~~~~~~~~~~~~~
+---------------------
 
 ``lsvirtualenv``
   List all of the environments.