fix(block): Ensure description has correct line-height (#6723)

**Related Issue:** #6443 

## Summary
The previous Tailwind text declaration wasn't setting a line-height,
meaning the description could unintentionally inherit line-height from a
parent container. This wasn't affecting the `collapsible` block as the
rendered button has additional style set that prevents the issue.

| Before      | After |
| ----------- | ----------- |
| <img width="460" alt="Screen Shot 2023-04-03 at 5 53 38 PM"
src="https://user-images.githubusercontent.com/4733155/229659153-e9cfb318-1bdc-4778-8545-12ff70d9c110.png">
| <img width="460" alt="Screen Shot 2023-04-03 at 5 53 47 PM"
src="https://user-images.githubusercontent.com/4733155/229659124-a4b4f3a6-b3c6-44d5-a89a-82032cf3d2bc.png">
|

src/components/block/block.scss

@@ -85,7 +85,7 @@ calcite-handle {
 }
 
 .description {
-  @apply text-n2
+  @apply text-n2-wrap
     text-color-3
     word-break
     mt-0.5