Website: Fix overflowing text on orchestration page. (#45722)

Changes:
- Fixed text overflowing outside of the page's container on the
/orchestration page

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## Summary by CodeRabbit

* **Bug Fixes**
* Improved responsive design on mobile devices—testimonial videos, hero
text, and feature text now scale fluidly while maintaining appropriate
maximum widths on smaller screens.

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website/assets/styles/pages/observability.less

@@ -479,13 +479,16 @@
       max-width: 840px;
     }
     [purpose='testimonial-videos'] {
-      width: 410px;
+      max-width: 410px;
+      width: 100%;
     }
     [purpose='hero-text'] {
-      width: 410px;
+      max-width: 410px;
+      width: 100%;
     }
     [purpose='feature-text'] {
-      width: 410px;
+      max-width: 410px;
+      width: 100%;
     }
   }