Override maxLength default value of 1024 for keywords in beats

[simitt]

Currently the default value for ignore_above is set to 1024 in the beats framework. Hence, we use the same limit on the Intake API for string data that are indexed as keywords to avoid issues when querying for it.

As explained in the ES docs the document itself would be indexed, but not the keyword field that exceeds the ignore_above limit.

[alvarolobato]

We need to discuss if we want/need to make this differently. Are there any use cases specific to this?

[simitt]

Questions came up here:
#801
#777

It doesn't seem to be an immediate or urgent request, so I suggest to keep the issue open so we can collect use cases but put it somewhere into the Inbox.

[graphaelli]

Can we close this since elastic/beats#7238 is in?

[graphaelli]

tested that ignore_above in fields.yml overrides the default of 1024 now