Import patterns from ECS

[jsoriano]

ECS fields can include patterns since elastic/ecs#1834, import them when available.

Validation was already implemented in #162.

Requested in #615 (comment).

[elasticmachine]

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• Start Time: 2022-04-01T16:11:15.097+0000

• Duration: 31 min 39 sec

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[jsoriano]

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[jsoriano]

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