🐛 Change Document Source default to `DS`

[ollyhensby]

Describe the bug
Document Source should be DS not WD:

document-issue/packages/document-issue/src/document_issue/document.py

Lines 83 to 88 in 807fd9d

	document_source: str = Field( # TODO: rename `document_source`
	"WD",
	description="software used to author the document",
	examples=DocSource._member_names_,
	alias="doc_source",
	)