Adds mention of fidelityfx-cas as requested by AMD (#629)

Author: JordanL8

com.unity.render-pipelines.high-definition/Documentation~/HDRP-Asset.md

@@ -75,7 +75,7 @@ These settings control the draw distance and resolution of the decals atlas that
 | ------------------------------- | ------------------------------------------------------------ |
 | **Enable**                      | Enable the checkbox to make HDRP support dynamic resolution in your Unity Project. |
 | **- Dynamic Resolution Type**   | Use the drop-down to select the type of dynamic resolution HDRP uses:<br />&#8226; **Software**: This option allocates render targets to accommodate the maximum resolution possible, then rescales the viewport accordingly. This allows the viewport to render at varying resolutions. |
-| **- Upscale Filter**            | Use the drop-down to select the filter that HDRP uses for upscaling.<br />&#8226; **Bilinear**: A low quality upsample. The least resource intensive option.<br />&#8226; **Catmull-Rom**: A bicubic upsample with 4 taps.<br />&#8226; **Lanczos**: A sharp upsample. This method can potentially introduce artifacts so you should not use it for extreme upsampling cases for example, when the screen percentage is less than 50%.<br />&#8226; **Contrast Adaptive Sharpen**: An ultra sharp upsample. Not meant for screen percenatage less than 50% and will still sharpen when screen percentage is set to 100% |
+| **- Upscale Filter**            | Use the drop-down to select the filter that HDRP uses for upscaling.<br />&#8226; **Bilinear**: A low quality upsample. The least resource intensive option.<br />&#8226; **Catmull-Rom**: A bicubic upsample with 4 taps.<br />&#8226; **Lanczos**: A sharp upsample. This method can potentially introduce artifacts so you should not use it for extreme upsampling cases for example, when the screen percentage is less than 50%.<br />&#8226; **Contrast Adaptive Sharpen**: An ultra sharp upsample. This option is not meant for screen percentages less than 50% and still sharpens when the screen percentage is set to 100%. This uses **FidelityFX (CAS) AMD™**. For information about FidelityFX and Contrast Adaptive Sharpening, see [AMD FidelityFX](https://www.amd.com/en/technologies/radeon-software-fidelityfx). |
 | **- Minimum Screen Percentage** | The minimum screen percentage that dynamic resolution can reach. |
 | **- Maximum Screen Percentage** | The maximum screen percentage that dynamic resolution can reach. This value must be higher than the **Min Screen Percentage**. |
 | **- Force Screen Percentage**   | Enable the checkbox to force HDRP to use a specific screen percentage for dynamic resolution. This feature is useful for debugging dynamic resolution. |