Incorrect doc type for `_WP_Dependency::$src`

[swissspidy]

When using wp_register_script with $src set to false, it means the item is an alias of other items it depends on.

Thus, it's possible for the _WP_Dependency object to have a $src that's not a string. This should be reflected in the docblock.

/**
 * The handle source.
 *
 * @since 2.6.0
 * @var string|false
 */
public $src;

[costdev]

[48462] documented $src as string, but did not include the false type.

Patch 57206.diff looks good to me - Thanks @mehulkaklotar!

Milestoning for 6.2 and adding for commit consideration.

[SergeyBiryukov]

In 54875:

Docs: Correct the type for _WP_Dependency::$src property.

The handle source can be set to false, which means the item is an alias of other items it depends on.

Follow-up to [7970], [25518], [43661], [47170], [48462], [54470].

Props mehulkaklotar, swissspidy, costdev.
Fixes #57206.