usage-data: missing event cols

Created by: coury-clark

Closes https://github.com/sourcegraph/sourcegraph/issues/39391

Adds columns to the event_logs table to match what is being scraped and set in the usage data event stream. This is necessary since this new job will scrape directly from the buffer table instead of forwarding events from the browser directly.

Test plan

To test locally:

Set up gcp credentials

gcloud auth application-default login

Start sg

GOOGLE_APPLICATION_CREDENTIALS="$HOME/.config/gcloud/application_default_credentials.json" sg start ...

Add configuration to the site config

    "exportUsageTelemetry": {
      "enabled": true,
      "topicProjectName": "sourcegraph-dogfood",
      "topicName": "usage-data-testing"
    },