Provide capability to configure SAS tokens via raw value or environment variable & don't log raw configuration

[tomkerkhove]

• Provide capability to configure SAS tokens via raw value or environment variable
• Don't log raw configuration to leak configured raw SAS token

Relates to #530 & #514

Metrics Configuration example

metrics:
  - name: demo_azurestoragequeue_queue_size
    description: "Approximate amount of messages in 'orders' queue (determined with StorageQueue provider)"
    resourceType: StorageQueue
    accountName: promitor
    queueName: orders
    sasToken:
      rawValue: "?sv=<redacted>"
    azureMetricConfiguration:
      metricName: MessageCount
      aggregation:
        type: Total
  - name: demo_azurestoragequeue_queue_timespentinqueue
    description: "Approximate amount of time that the oldest message has been in 'orders' queue (determined with StorageQueue provider)"
    resourceType: StorageQueue
    accountName: promitor
    queueName: orders
    sasToken:
      environmentVariable: SECRETS_STORAGEQUEUE_SAS
    azureMetricConfiguration:
      metricName: TimeSpentInQueue
      aggregation:
        type: Total

[promitor-bot]

Docker image for this PR was built and is available on Docker Hub.

You can pull it locally via the CLI:

docker pull tomkerkhove/promitor-agent-scraper-ci:pr531

Want to verify the new version? Run it locally:

docker run -d -p 8999:80 --name promitor-agent-scraper-pr531 \
                         --env PROMITOR_AUTH_APPID='<azure-ad-app-id>' \
                         --env-file C:/Promitor/az-mon-auth.creds\
                         --volume C:/Promitor/metrics-declaration.yaml:/config/metrics-declaration.yaml \
                         tomkerkhove/promitor-agent-scraper-ci:pr531