test: remove RxJS from E2E process utility #2651

Job	Run time
list	41s
workflow (devkit-core-tests)	1m 28s
workflow (modules-builder-tests)	1m 58s
workflow (build-unit-tests)	2m 15s
workflow (build-cli)	1m 46s
workflow (devkit-core-tests-rerun)	1m 24s
	9m 32s

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