[Docs] Improve Related Docs Links in Pinning Models to Dock Page

#### Current State
In the Related Docs section of the Pinning Models to Dock [page](https://docs.layer5.io/videos/getting-started/basics/pinning-models-to-dock/) , the documentation link is displayed as a raw URL instead of a readable hyperlink text.

#### Desired State

- Convert the existing raw URL into a readable hyperlink named "Understanding Tool Modes".
- Add another hyperlink named "Pin Model to Dock" pointing to:
https://docs.layer5.io/kanvas/designer/pin-model-to-dock/ since it is also related to this topic.

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