Use fixed, mock credentials in emfexporter test. (#1176)
Use fixed, mock credentials in emfexporter test. (#1176)

Set environment variables for AWS credentials to mock values. From what I can tell, the test fails if someone has valid AWS credentials on their machine currently, so to make behavior consistent we need the test to setup fixed creds.

Fixes #1149

open-telemetry/opentelemetry-collector-contrib,open-telemetry/opentelemetry-collector-contrib