* fix fileutils.TestFindFile on MacOS
* introduce model.ExternalServiceEnvironment
* pick license public key from external service env
* pick Stripe public key from external service env
* pick Rudder key from external service env
* configure Sentry DSN from external service env
* always log external_service_environment, Unsetenv
* clear faked BuildEnv, improve logging
* strip out unset GOTAGS
* fix Sentry tests
* simplify to just ServiceEnvironment
* relocate ServiceEnvironment in client config
* initialize CWS URLs based on service environment
* unset rudder key for boards dev
* harden service environment to avoid accidental production
* fix TestSentry again
* fix DEFAULT -> ENTERPRISE
* s/dev/test when naming playbooks rudder key
* simplify boards rudder key switch
* use uniform rudderKey variable names
* retain compatibility with existing pipeline
* reduce to just production/test
* unit test with valid test license
* simplify Playbooks telemetry initialization
* restore dev service environment
* emit ServiceEnvironment when running e2e tests
