add performance log for stem view in UI

grouper.log.performance.info.on.StemUiView = true

2022-03-01T02:26:56,741: [http-nio-8400-exec-8] INFO  UiV2Stem.viewStem(975) - [] - performanceLogFor: StemUiView, sqlQueries_durationMs: 146, findStem_elapsedMs: 4, sqlQueries_count: 19, stemPrivilege_elapsedMs: 7, setupAttestation_elapsedMs: 9, pre_viewStem.jsp_elapsedMs: 9, pre_moreActionsButton_elapsedMs: 51, getTemplatesToShowInMoreActions_durationMs: 96, getTemplatesToShowInMoreActions_count: 2, post_moreActionsButton_elapsedMs: 192, post_viewStemInJsp_elapsedMs: 196, post_viewStem.jsp_elapsedMs: 196, preFilterHelper_elapsedMs: 196, pre_browseObjectFilter_elapsedMs: 196, pre_stemContents.jsp_elapsedMs: 309, post_stemContents.jsp_elapsedMs: 312, postFilterHelper_elapsedMs: 312, took_elapsedMs: 312