Fix a small typo in user_guide/installation
Just walked through the signup process again, and I think I found a small typo near the top of the installation instructions.
@@ -5,7 +5,7 @@ Installation
Python
------
-Before installing the SiliconCompiler package you will need to set up a Python environment. Currently Python 3-6-3.10 is supported.
+Before installing the SiliconCompiler package you will need to set up a Python environment. Currently Python 3.6-3.10 is supported.
Ubuntu (>=18.04)
^^^^^^^^^^^^^^^^
