test: fix editor-best-of-n e2e test to check sessionState for impleme… #5258

Job	Run time
build-and-check	2m 43s
test-packages/billing	36s
test-.agents	46s
test-common	42s
test-integration-sdk	39s
test-web	50s
test-sdk	47s
test-cli	1m 10s
test-integration-packages/agent-runtime	47s
test-integration-common	41s
test-packages/internal	45s
test-integration-.agents	47s
test-integration-packages/billing	42s
test-integration-cli	40s
test-integration-web	39s
test-integration-packages/internal	47s
test-packages/agent-runtime	52s
	14m 53s

Provide feedback