Docs: clarify quoting in version specs note

Previously it was confusing as to what `" "` meant exactly -- I read it
as a whitespace character was needed somewhere when it's referring to
the double quote characters.

docs/basics.rst

@@ -203,7 +203,7 @@ To make inclusive or exclusive version comparisons you can use: ::
     $ pipenv install "requests<=2.13"  # will install a version equal or lower than 2.13.0
     $ pipenv install "requests>2.19"   # will install 2.19.1 but not 2.19.0 
 
-.. note:: The use of ``" "`` around the package and version specification is highly recommended 
+.. note:: The use of double quotes around the package and version specification (i.e. ``"requests>2.19"``) is highly recommended
     to avoid issues with `Input and output redirection <https://robots.thoughtbot.com/input-output-redirection-in-the-shell>`_
     in Unix-based operating systems.