fix: allow overriding enabled/retestOnFailure via global config

[vigneshshanmugam]

• fix Global monitor options enabled and retestOnFailure are ignored #894
• enabled: false and retestOnFailure: false on the synthetics global config did not get passed to Kibana which effectively meant the users can only enable/disable them via individual monitor config. This PR fixes the problem and allows all monitors to be overridden with correct value.

[devcorpio]

LGTM

--

Tested with this global monitor settings:

    // ...
    /**
     * Configure global monitor settings
     */
    monitor: {
      schedule: 5,
      locations: ['local_synthetics_service'] as any,
      privateLocations: [],
      tags: ['']
      enabled: false,
      throttling: false,
      retestOnFailure: false,
    },

   // ...

before the change:

after the change: