Fix Parsing of Multiline Argument Descriptions

[shreya0204]

Fixes: #477

This pull request addresses a parsing error in the WP CLI handbook where multiline argument descriptions in the Utils\http_request() method were not being handled correctly. Previously, the parser failed to recognize , as a valid character that could indicate the continuation of an argument description onto a new line.

Changes Made:

Updated the conditional check in the parsing logic. Now, the parser recognizes both { and , characters as potential indicators of a multiline argument. This ensures that argument descriptions that continue after these characters are correctly parsed and included in the documentation.