Fix test_dashboards in x-pack metricbeat

[jsoriano]

See #26526

Failure seems to be caused by Metricbeat-aws-billing-overview.json dashboard.

Can be reproduced with the following command from x-pack/metricbeat.

PYTEST_ADDOPTS="-k test_dashboards" mage pythonIntegTest

Trace:

E         2021-06-28T15:03:22.125Z	ERROR	instance/beat.go:971	Exiting: Failed to import dashboard: Failed to load directory /go/src/github.com/elastic/beats/x-pack/metricbeat/build/system-tests/run/test_xpack_base.Test.test_dashboards/kibana/7/dashboard:
E           error loading /go/src/github.com/elastic/beats/x-pack/metricbeat/build/system-tests/run/test_xpack_base.Test.test_dashboards/kibana/7/dashboard/Metricbeat-aws-billing-overview.json: returned 500 to import file: <nil>. Response: {"statusCode":500,"error":"Internal Server Error","message":"An internal server error occurred."}
E         Exiting: Failed to import dashboard: Failed to load directory /go/src/github.com/elastic/beats/x-pack/metricbeat/build/system-tests/run/test_xpack_base.Test.test_dashboards/kibana/7/dashboard:
E           error loading /go/src/github.com/elastic/beats/x-pack/metricbeat/build/system-tests/run/test_xpack_base.Test.test_dashboards/kibana/7/dashboard/Metricbeat-aws-billing-overview.json: returned 500 to import file: <nil>. Response: {"statusCode":500,"error":"Internal Server Error","message":"An internal server error occurred."}
E         
E       assert 1 == 0

[elasticmachine]

Pinging @elastic/integrations (Team:Integrations)

[blakerouse]

This is blocking my progress on #26665? Is there an update on this? Can we skip the test?

[kaiyan-sheng]

@blakerouse Not sure if I can only skip certain dashboard from this pythonIntegTest. I will look into how to fix it today.

[kaiyan-sheng]

@blakerouse btw x-pack/metricbeat test dashboard is already disabled in PR #26537. Do you need to reenable the test for your PR?

[blakerouse]

@kaiyan-sheng I am seeing this error with last merge of master into my PR. Seems like the exact same issue that is reported here.

https://beats-ci.elastic.co/blue/organizations/jenkins/Beats%2Fbeats/detail/PR-26665/15/

[kaiyan-sheng]

Thanks for the link! It's the same problem but happening under beats/metricbeat instead of beats/x-pack/metricbeat. Maybe #26972 will fix it!