Use updated URLs for contribution guidelines

Signed-off-by: Keshav Priyadarshi <git@keshav.space>

Author: keshav-space

docs/source/contributing.rst

@@ -17,7 +17,7 @@ resources to help you get started.
 Do Your Homework
 ----------------
 
-Before adding a contribution or create a new issue, take a look at the project’s
+Before adding a contribution or create a new issue, take a look at the project's
 `README <https://github.com/aboutcode-org/vulnerablecode>`_, read through our
 `documentation <https://vulnerablecode.readthedocs.io/en/latest/>`_,
 and browse existing `issues <https://github.com/aboutcode-org/vulnerablecode/issues>`_,
@@ -73,7 +73,7 @@ overlooked. We value any suggestions to improve
 
 .. tip::
     Our documentation is treated like code. Make sure to check our
-    `writing guidelines <https://scancode-toolkit.readthedocs.io/en/latest/contribute/contrib_doc.html>`_
+    `writing guidelines <https://scancode-toolkit.readthedocs.io/en/stable/contribute/contrib_doc.html>`_
     to help guide new users.
 
 Other Ways
@@ -87,7 +87,7 @@ questions, and interact with us and other community members on
 Helpful Resources
 -----------------
 
-- Review our `comprehensive guide <https://scancode-toolkit.readthedocs.io/en/latest/contribute/index.html>`_
+- Review our `comprehensive guide <https://scancode-toolkit.readthedocs.io/en/stable/contribute/index.html>`_
   for more details on how to add quality contributions to our codebase and documentation
 - Check this free resource on `How to contribute to an open source project on github <https://egghead.io/lessons/javascript-identifying-how-to-contribute-to-an-open-source-project-on-github>`_
 - Follow `this wiki page <https://aboutcode.readthedocs.io/en/latest/contributing/writing_good_commit_messages.html>`_