[Breaking Change] Updated documentation and modified InternalChecker message parameters.

[yoshi-automation]

This PR was generated using Autosynth. 🌈

Here's the log from Synthtool:

synthtool > Cloning googleapis.
synthtool > Running generator for google/monitoring/artman_monitoring.yaml.
synthtool > Ensuring dependencies.
synthtool > Pulling artman image.
synthtool > Generated code into /home/kbuilder/.cache/synthtool/googleapis/artman-genfiles/php/google-cloud-monitoring-v3.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/Gapic/GroupServiceGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/GroupServiceClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/Gapic/MetricServiceGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/MetricServiceClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/Gapic/UptimeCheckServiceGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/UptimeCheckServiceClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/Gapic/AlertPolicyServiceGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/AlertPolicyServiceClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/Gapic/NotificationChannelServiceGapicClient.php.
synthtool > Replaced 'Copyright \\d{4}' in src/V3/NotificationChannelServiceClient.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/System/V3/MetricServiceSmokeTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V3/AlertPolicyServiceClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V3/UptimeCheckServiceClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V3/GroupServiceClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V3/MetricServiceClientTest.php.
synthtool > Replaced 'Copyright \\d{4}' in tests/Unit/V3/NotificationChannelServiceClientTest.php.
synthtool > Replaced 'ListTimeSeriesRequest_TimeSeriesView' in src/V3/Gapic/MetricServiceGapicClient.php.
synthtool > Cleaned up 1 temporary directories.

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