Refine Has pipeline status check in E2E specs

What does this MR do?

Follow-up on discussion in !65159 (comment 615667180), updating has_pipeline_status? texts to use passed instead of /Pipeline #\d+ passed/. All thanks to @treagitlab's vigilance:

has_pipeline_status? looks within :merge_request_pipeline_info_content which is this section. And we can see that the text can be different, in this case pipeline isn't capitalized, if the same expectation applied here, this will fail. The word passed; however, is the same in all the cases as far as I'm aware of, and I do think it is sufficient by itself. image

Check-list

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