feat: add msc4028 to versions api #226

Job	Run time
changes	2s
check-lockfile	4s
lint-crlf	4s
lint-newsfile	35s
check-sampleconfig	36s
Typechecking	1m 6s
check-schema-delta	38s
lint	58s
lint-pydantic	2m 51s
lint-clippy	0s
lint-clippy-nightly	0s
lint-rustfmt	0s
linting-done	3s
calculate-test-jobs	4s
trial-olddeps	6m 39s
complement (monolith, SQLite)	12m 25s
portdb (3.8, 11)	2m 54s
trial-pypy	0s
complement (monolith, Postgres)	13m 0s
portdb (3.11, 15)	2m 32s
complement (workers, Postgres)	20m 1s
cargo-bench	0s
cargo-test	0s
sytest (focal)	8m 19s
sytest (focal, postgres)	10m 0s
trial (3.8, sqlite, all)	4m 11s
sytest (focal, multi-postgres, workers)	13m 34s
trial (3.8, postgres, 11, all)	9m 43s
sytest (focal, multi-postgres, workers, asyncio)	18m 57s
trial (3.8, sqlite)	4m 6s
export-data	1m 58s
tests-done	2s
	2h 15m 22s

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