Use quoted variabled for path with spaces

If $PWD contains spaces, the command breaks without quotes.

Signed-off-by: Hritik V <hey@hritik.sh>

Author: Hritik14

docs/source/getting-started/installation/install-scancode-using-docker.rst

@@ -64,7 +64,7 @@ apache-2.0.LICENSE directory. The JSON results will be in scan-result.json
 
 .. code-block:: shell
 
-    docker run -v $PWD/:/project scancode-toolkit -clipeu --json-pp /project/scan-result.json /project/apache-2.0.LICENSE
+    docker run -v "$PWD/:/project" scancode-toolkit -clipeu --json-pp /project/scan-result.json /project/apache-2.0.LICENSE
 
 This will mount your current working from the host into ``/project`` in the container
 and then scan the contents. The output ``result.json`` will be written back to your