Update block-patterns.md (#27520)

Added the required types for the categories, keywords, and viewportWidth arguments.

docs/designers-developers/developers/block-api/block-patterns.md

@@ -14,9 +14,9 @@ The properties of the block pattern include:
  - `title` (required): A human-readable title for the pattern.
  - `content` (required): Raw HTML content for the pattern.
  - `description`: A visually hidden text used to describe the pattern in the inserter. A description is optional but it is strongly encouraged when the title does not fully describe what the pattern does.
- - `categories`: A list of pattern categories used to group block patterns. Block patterns can be shown on multiple categories.
- - `keywords`: Aliases or keywords that help users discover it while searching.
- - `viewportWidth`: Specify the width of the pattern in the inserter.
+ - `categories`: An array of pattern categories used to group block patterns. Block patterns can be shown on multiple categories.
+ - `keywords`: An array of aliases or keywords that help users discover the pattern while searching.
+ - `viewportWidth`: An integer specifying the width of the pattern in the inserter.
 
 ```php
 register_block_pattern(