Toolset 3.0.4, SEMoS 1.8.8 released

[Alex Cabal]

Toolset version 3.0.4 and SEMoS 1.8.8 have been released.

Use `pipx upgrade standardebooks` to upgrade the toolset.

This release aligns our practices with the current draft of the epub
spec's structural semantics vocabulary. In particular, items like
ordinal, label, bridgehead, and endnote were removed in the current
draft. This affects our process in the following ways:

- Instead of `ordinal`, use `z3998:ordinal`

- Instead of `label`, use `se:label`.

- Instead of `bridgehead`, use `se:bridgehead`.

- Don't use `epub:type="endnote"` for individual endnotes. Individual
endnotes are now defined by the CSS selector
`section[epub|type~="endnotes"] > ol > li` and don't have special semantics.

If you currently have an ebook in progress, then you don't have to make
these updates yourself; just finish the ebook as usual and I'll make
these updates on my end before releasing it.

Full changelog:

# 3.0.4

## General

- Use the latest epub structural semantics vocabulary across the toolset

## se clean

- Alphabetize `epub:type` values

## se create-draft

- Add semantics to name with Jr. and remove duplicate terminal periods

- Update to new PG link style

## se lint

- Improve t-008

- Improve s-068

- Improve t-011

- Check for dedicator role. Thanks to Robin Whittleton

- Add t-005, newspaper name not in italics

- Add s-108, `<thead>` element with non-empty `<td>` descendant

## se modernizes-spelling

- Various additions

## se semanticate

- Add semantics to Jr.

- Consolidate some regexes

- Don’t add initialism to compass semantics. Thanks to Robin Whittleton

## se split-file

- Don't crash if there are two or more `se:split` elements in a row