Update complement.sh to match new public API shape

[kegsay]

Sister PR to matrix-org/complement#666

Context: matrix-org/complement#654 (comment)

Pull Request Checklist

• Pull request is based on the develop branch
• Pull request includes a changelog file. The entry should:
  • Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from EventStore to EventWorkerStore.".
  • Use markdown where necessary, mostly for code blocks.
  • End with either a period (.) or an exclamation mark (!).
  • Start with a capital letter.
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• Pull request includes a sign off
• Code style is correct
  (run the linters)

[DMRobertson]

Try adding the complement.sh script in

synapse/.github/workflows/tests.yml

Lines 50 to 58 in a6abee3

	integration:
	- 'synapse/**'
	- 'rust/**'
	- 'docker/**'
	- 'Cargo.toml'
	- 'Cargo.lock'
	- 'pyproject.toml'
	- 'poetry.lock'
	- 'docker/**'

to make sure CI actually runs here. (C.f. #14745 and friends)

[kegsay]

It runs now, and fails the same failing tests on develop, which means it is in fact running those MSCs.

[DMRobertson]

Otherwise LGTM, thanks! I'll let you merge in tandem with the complement and Dendrite change.