feat: support SYNTHETICS_API_KEY env variable for auth

[shahzad31]

read auth from SYNTHETICS_API_KEY if available

[apmmachine]

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• Start Time: 2022-09-09T18:24:44.535+0000

• Duration: 13 min 5 sec

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🤖 GitHub comments

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[vigneshshanmugam]

Also, if we are doing this, then need to change the project generation command a bit differently.

We can remove this -

synthetics/src/generator/index.ts

Line 264 in 5d4ccc0

pkgJSON.scripts.push = `npx @elastic/synthetics push --auth $SYNTHETICS_API_KEY`;