doc(swift): build swift documentation in CI [WPB-16474]

[coriolinus]

What's new in this PR

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PR Submission Checklist for internal contributors

• The PR Title
  • [x] conforms to the style of semantic commits messages¹ supported in Wire's Github Workflow²
  • [x] contains a reference JIRA issue number like SQPIT-764
  • [x] answers the question: If merged, this PR will: ... ³

1. https://sparkbox.com/foundry/semantic_commit_messages
2. https://github.com/wireapp/.github#usage
3. E.g. feat(conversation-list): Sort conversations by most emojis in the title #SQPIT-764.

[github-actions[bot]]

Bencher Report

Branch	prgn/build/16474-swift-docs
Testbed	ubuntu-latest

Click to view all benchmark results

Benchmark	Latency	milliseconds (ms)
Commit add f(group size)/cs1/mem/1002	📈 view plot 🚷 view threshold	20.02 ms
Commit add f(group size)/cs1/mem/2	📈 view plot 🚷 view threshold	5.22 ms
Commit add f(group size)/cs1/mem/202	📈 view plot 🚷 view threshold	8.32 ms
Commit add f(group size)/cs1/mem/402	📈 view plot 🚷 view threshold	11.45 ms
Commit add f(group size)/cs1/mem/602	📈 view plot 🚷 view threshold	14.99 ms
Commit add f(group size)/cs1/mem/802	📈 view plot 🚷 view threshold	17.51 ms
Commit add f(number clients)/cs1/mem/1002	📈 view plot 🚷 view threshold	987.41 ms
Commit add f(number clients)/cs1/mem/2	📈 view plot 🚷 view threshold	5.18 ms
Commit add f(number clients)/cs1/mem/202	📈 view plot 🚷 view threshold	83.45 ms
Commit add f(number clients)/cs1/mem/402	📈 view plot 🚷 view threshold	219.79 ms
Commit add f(number clients)/cs1/mem/602	📈 view plot 🚷 view threshold	432.46 ms
Commit add f(number clients)/cs1/mem/802	📈 view plot 🚷 view threshold	676.05 ms
Commit pending proposals f(group size)/cs1/mem/1002	📈 view plot 🚷 view threshold	118.27 ms
Commit pending proposals f(group size)/cs1/mem/2	📈 view plot 🚷 view threshold	27.15 ms
Commit pending proposals f(group size)/cs1/mem/202	📈 view plot 🚷 view threshold	45.35 ms
Commit pending proposals f(group size)/cs1/mem/402	📈 view plot 🚷 view threshold	60.72 ms
Commit pending proposals f(group size)/cs1/mem/602	📈 view plot 🚷 view threshold	80.28 ms
Commit pending proposals f(group size)/cs1/mem/802	📈 view plot 🚷 view threshold	95.62 ms
Commit pending proposals f(pending size)/cs1/mem/1	📈 view plot 🚷 view threshold	19.78 ms
Commit pending proposals f(pending size)/cs1/mem/101	📈 view plot 🚷 view threshold	117.39 ms
Commit pending proposals f(pending size)/cs1/mem/21	📈 view plot 🚷 view threshold	36.88 ms
Commit pending proposals f(pending size)/cs1/mem/41	📈 view plot 🚷 view threshold	58.16 ms
Commit pending proposals f(pending size)/cs1/mem/61	📈 view plot 🚷 view threshold	77.51 ms
Commit pending proposals f(pending size)/cs1/mem/81	📈 view plot 🚷 view threshold	97.35 ms
Commit remove f(group size)/cs1/mem/1002	📈 view plot 🚷 view threshold	26.17 ms
Commit remove f(group size)/cs1/mem/2	📈 view plot 🚷 view threshold	5.01 ms
Commit remove f(group size)/cs1/mem/202	📈 view plot 🚷 view threshold	7.21 ms
Commit remove f(group size)/cs1/mem/402	📈 view plot 🚷 view threshold	10.53 ms
Commit remove f(group size)/cs1/mem/602	📈 view plot 🚷 view threshold	15.82 ms
Commit remove f(group size)/cs1/mem/802	📈 view plot 🚷 view threshold	20.33 ms
Commit remove f(number clients)/cs1/mem/1002	📈 view plot 🚷 view threshold	28.42 ms
Commit remove f(number clients)/cs1/mem/2	📈 view plot 🚷 view threshold	137.87 ms
Commit remove f(number clients)/cs1/mem/202	📈 view plot 🚷 view threshold	115.36 ms
Commit remove f(number clients)/cs1/mem/402	📈 view plot 🚷 view threshold	92.81 ms
Commit remove f(number clients)/cs1/mem/602	📈 view plot 🚷 view threshold	70.97 ms
Commit remove f(number clients)/cs1/mem/802	📈 view plot 🚷 view threshold	49.45 ms
Commit update f(group size)/cs1/mem/1002	📈 view plot 🚷 view threshold	137.27 ms
Commit update f(group size)/cs1/mem/2	📈 view plot 🚷 view threshold	5.26 ms
Commit update f(group size)/cs1/mem/202	📈 view plot 🚷 view threshold	32.37 ms
Commit update f(group size)/cs1/mem/402	📈 view plot 🚷 view threshold	58.69 ms
Commit update f(group size)/cs1/mem/602	📈 view plot 🚷 view threshold	85.87 ms
Commit update f(group size)/cs1/mem/802	📈 view plot 🚷 view threshold	111.90 ms

🐰 View full continuous benchmarking report in Bencher

[coriolinus]

Obsoleted by #1219 .