Fix small typo in README

[csuarez]

Just a missing comma in the configuration example.

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[csuarez]

I signed it!

[googlebot]

CLAs look good, thanks!

[hicom150]

Looks good to me 👍
@johnjbarton would be convenient to merge this PR?

[johnjbarton]

@johnjbarton would be convenient to merge this PR?

I think you should press "Squash and merge"