fix(ci): use yarn for example repo dep installs

[amirrustam]

No description provided.

[cypress-bot]

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[cypress]

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Test summary

9384 • 0 • 119 • 3 • 1

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Run details

Project	cypress
Status	Passed
Commit	e948f61
Started	Mar 12, 2021 11:55 PM
Ended	Mar 13, 2021 12:06 AM
Duration	10:47 💡
OS	Linux Debian - 10.5
Browser	Multiple

View run in Cypress Dashboard ➡️

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Flakiness

	cypress/integration/retries.ui.spec.js		1
1	runner/cypress retries.ui.spec > opens attempt on each attempt failure for the screenshot, and closes after test passes

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