docs: Update readme to link the new Custom Modes video (#9000)

Co-authored-by: ellipsis-dev[bot] <65095814+ellipsis-dev[bot]@users.noreply.github.com>
Co-authored-by: Sannidhya <[email protected]>

Author: 3 people

README.md

@@ -69,7 +69,7 @@ Learn more: [Using Modes](https://docs.roocode.com/basic-usage/using-modes) •
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 | <a href="https://www.youtube.com/watch?v=Mcq3r1EPZ-4"><img src="https://img.youtube.com/vi/Mcq3r1EPZ-4/maxresdefault.jpg" width="100%"></a><br><b>Installing Roo Code</b> | <a href="https://www.youtube.com/watch?v=ZBML8h5cCgo"><img src="https://img.youtube.com/vi/ZBML8h5cCgo/maxresdefault.jpg" width="100%"></a><br><b>Configuring Profiles</b> | <a href="https://www.youtube.com/watch?v=r1bpod1VWhg"><img src="https://img.youtube.com/vi/r1bpod1VWhg/maxresdefault.jpg" width="100%"></a><br><b>Codebase Indexing</b> |
-|    <a href="https://www.youtube.com/watch?v=qgqceCuhlRA"><img src="https://img.youtube.com/vi/qgqceCuhlRA/maxresdefault.jpg" width="100%"></a><br><b>Custom Modes</b>     |     <a href="https://www.youtube.com/watch?v=Ho30nyY332E"><img src="https://img.youtube.com/vi/Ho30nyY332E/maxresdefault.jpg" width="100%"></a><br><b>Checkpoints</b>      |    <a href="https://www.youtube.com/watch?v=6h5vB9PpoPk"><img src="https://img.youtube.com/vi/6h5vB9PpoPk/maxresdefault.jpg" width="100%"></a><br><b>Todo Lists</b>     |
+|    <a href="https://www.youtube.com/watch?v=iiAv1eKOaxk"><img src="https://img.youtube.com/vi/iiAv1eKOaxk/maxresdefault.jpg" width="100%"></a><br><b>Custom Modes</b>     |     <a href="https://www.youtube.com/watch?v=Ho30nyY332E"><img src="https://img.youtube.com/vi/Ho30nyY332E/maxresdefault.jpg" width="100%"></a><br><b>Checkpoints</b>      |    <a href="https://www.youtube.com/watch?v=6h5vB9PpoPk"><img src="https://img.youtube.com/vi/6h5vB9PpoPk/maxresdefault.jpg" width="100%"></a><br><b>Todo Lists</b>     |
 
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