Bump e2e test server constraints

Author: shevisj

e2e-test-server/constraints.txt

@@ -16,7 +16,7 @@ Jinja2==2.11.3
 libcst==0.3.18
 MarkupSafe==1.1.1
 mypy-extensions==0.4.3
-opentelemetry-api==1.1.0
+opentelemetry-api==1.4.0
 opentelemetry-sdk==1.1.0
 opentelemetry-semantic-conventions==0.20b0
 packaging==20.9