[8.0](backport #30014) Updated dev guide instructions to work with master

[mergify]

This is an automatic backport of pull request #30014 done by Mergify.

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[elasticmachine]

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• Reason: null

• Start Time: 2022-02-01T13:37:28.442+0000

• Duration: 20 min 10 sec

• Commit: 533983e

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