Add YouTube videos to tutorials

Signed-off-by: Gigon Bae <gbae@nvidia.com>

Author: gigony

docs/source/getting_started/tutorials/01_simple_app.md

@@ -19,9 +19,18 @@ jupyter-lab
 ../../notebooks/tutorials/01_simple_app.ipynb
 ```
 
+<!-- It is not centered with {link-button} ...
 ```{link-button} ../../_static/notebooks/tutorials/01_simple_app.ipynb
 :text: Download 01_simple_app.ipynb
 :classes: btn-outline-primary col-md-6
+``` -->
+
+```{raw} html
+<p style="text-align: center;">
+    <a class="sphinx-bs btn text-wrap btn-outline-primary col-md-6 reference external" href="../../_static/notebooks/tutorials/01_simple_app.ipynb">
+        <span>Download 01_simple_app.ipynb</span>
+    </a>
+</p>
 ```
 
 ## Executing from Shell

docs/source/getting_started/tutorials/02_mednist_app.md

@@ -19,9 +19,12 @@ jupyter-lab
 ../../notebooks/tutorials/02_mednist_app.ipynb
 ```
 
-```{link-button} ../../_static/notebooks/tutorials/02_mednist_app.ipynb
-:text: Download 02_mednist_app.ipynb
-:classes: btn-outline-primary col-md-6
+```{raw} html
+<p style="text-align: center;">
+    <a class="sphinx-bs btn text-wrap btn-outline-primary col-md-6 reference external" href="../../_static/notebooks/tutorials/02_mednist_app.ipynb">
+        <span>Download 02_mednist_app.ipynb</span>
+    </a>
+</p>
 ```
 
 ## Executing from Jupyter Notebook (Using a Prebuilt Model)
@@ -32,9 +35,18 @@ jupyter-lab
 ../../notebooks/tutorials/02_mednist_app-prebuilt.ipynb
 ```
 
-```{link-button} ../../_static/notebooks/tutorials/02_mednist_app-prebuilt.ipynb
-:text: Download 02_mednist_app-prebuilt.ipynb
-:classes: btn-outline-primary btn-block col-md-6
+```{raw} html
+<div style="text-align: center;">
+    <iframe width="560" height="315" src="https://www.youtube.com/embed/WwjilJFHuU4" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+</div>
+```
+
+```{raw} html
+<p style="text-align: center;">
+    <a class="sphinx-bs btn text-wrap btn-outline-primary col-md-6 reference external" href="../../_static/notebooks/tutorials/02_mednist_app-prebuilt.ipynb">
+        <span>Download 02_mednist_app-prebuilt.ipynb</span>
+    </a>
+</p>
 ```
 
 ## Executing from Shell

docs/source/getting_started/tutorials/03_segmentation_app.md

@@ -19,9 +19,24 @@ jupyter-lab
 ../../notebooks/tutorials/03_segmentation_app.ipynb
 ```
 
-```{link-button} ../../_static/notebooks/tutorials/03_segmentation_app.ipynb
-:text: Download 03_segmentation_app.ipynb
-:classes: btn-outline-primary col-md-6
+```{raw} html
+<div style="text-align: center;">
+    <iframe width="560" height="315" src="https://www.youtube.com/embed/cqDVxzYt9lY" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+</div>
+```
+
+```{raw} html
+<div style="text-align: center;">
+    <iframe width="560" height="315" src="https://www.youtube.com/embed/nivgfD4pwWE" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+</div>
+```
+
+```{raw} html
+<p style="text-align: center;">
+    <a class="sphinx-bs btn text-wrap btn-outline-primary col-md-6 reference external" href="../../_static/notebooks/tutorials/03_segmentation_app.ipynb">
+        <span>Download 03_segmentation_app.ipynb</span>
+    </a>
+</p>
 ```
 
 ## Executing from Shell