Switch to linkcode extension

[ankatiyar]

Description

Resolve #4174

Development notes

Switched from sphinx.ext.viewcode --> sphinx.ext.linkcode, which required adding a linkcode_resolve() function to the conf.py (code copied from/inspired by other docs that use the extension)

This is what it should look like in the API docs ->

When you click on the "[source]", it should take you to kedro's repo for the code

Developer Certificate of Origin

We need all contributions to comply with the Developer Certificate of Origin (DCO). All commits must be signed off by including a Signed-off-by line in the commit message. See our wiki for guidance.

If your PR is blocked due to unsigned commits, then you must follow the instructions under "Rebase the branch" on the GitHub Checks page for your PR. This will retroactively add the sign-off to all unsigned commits and allow the DCO check to pass.

Checklist

• Read the contributing guidelines
• Signed off each commit with a Developer Certificate of Origin (DCO)
• Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• Updated the documentation to reflect the code changes
• Added a description of this change in the RELEASE.md file
• Added tests to cover my changes
• Checked if this change will affect Kedro-Viz, and if so, communicated that with the Viz team

[ElenaKhaustova]

Works like a magic 👍

[ElenaKhaustova]

Shall we make the same for Viz/datasets docs?

[astrojuanlu]

Finally 😭 Thanks a lot @ankatiyar ! And as @ElenaKhaustova says, let's do the same for all subprojects

[ankatiyar]

Finally 😭 Thanks a lot @ankatiyar ! And as @ElenaKhaustova says, let's do the same for all subprojects

I'll do separate PRs and keep the issue open :)