Send e2e test results to Buildkite TestAnalystics

[twometresteve]

Goal

Send Maze Runner test results to Buildkite TestAnalytics.

Design

1. Output tests results from Maze Runner in Junit XML format using the --format option (has to be given twice to avoid losing the default pretty output).
2. Use the test-collector Buildkite pluging to send the results on - this needs the API key to be set in the BUILDKITE_ANALYTICS_TOKEN environment variable, which I've done in our s3 bucket.

Testing

I've run a full build to make sure I've not broken the pipeline YAML, but it can't be tested fully until it's on next.

[bugsnagbot]

Android notifier sizes

Format	Size impact of Bugsnag (kB)	Size impact of Bugsnag when Minified (kB)
APK	1853.94	1674.71
arm64_v8a	631.04	450.82
armeabi_v7a	565.51	385.29
x86	708.85	528.62
x86_64	676.09	495.86

Generated by 🚫 Danger