Backend.Tests: acceptance t for bug 242's 1st part #2909

Job	Run time
windows--dotnet6-and-legacyFramework	2m 57s
macOS--mono-only	5m 29s
macOS--dotnet6-only	2m 44s
macOS--dotnet6-and-mono	2m 44s
linux22-vanilla--stockdotnet6-only	1m 57s
linux22-github--dotnet-and-mono	2m 9s
linux22-vanilla--stockmono-only	4m 40s
windows--dotnet6-only	2m 59s
linux20-github--dotnet-and-mono	1m 39s
windows--legacyFramework-only	14m 15s
linux20-github--dotnet-and-newmono	1m 57s
linux20-vanilla--newmono-only	5m 56s
linux20-vanilla--stockmono-only	4m 56s
linux22-github--dotnet-and-newmono	1m 43s
linux22-vanilla--newmono-only	5m 40s
linux22-vanilla--stockdotnet6-and-newmono	2m 43s
linux22-vanilla--stockdotnet6-and-stockmono	1m 59s
conventions	0s
snap_pkg	0s
	1h 6m 27s

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