Add `ProcessGuarantee` to WindowConfig #723

Job	Run time
integration (integration test, .ci/tests/integration/e2e.yaml)	1m 49s
integration (integration test with tls, .ci/tests/integration/e2e_with_tls.yaml)	1m 55s
integration (integration test with oauth2, .ci/tests/integration-oauth2/e2e.yaml)	1m 38s
integration (integration test with downloader, .ci/tests/integration-oauth2/e2e_with_downloader.y...	1m 49s
	7m 11s

Provide feedback