[12.x] Remove return void from Http\Client\Batch's constructor

[rodrigopedra]

@return void was removed from class constructors' docblocks framework-wise in PR #55076.

There seems to have been an oversight on the PR that introduced the Illuminate\Http\Client\Batch class, which included that param in that class constructor's docblock.

This PR:

• Removes the @return void docblock from the Illuminate\Http\Client\Batch class constructor docblock.