Make GitHub Actions warning when win-scons tests fail

.github/workflows/ci.yml

@@ -155,6 +155,12 @@
 					name: build and unit test,
 					run: '.\.github\workflows\scripts\win\scons-build.bat'
 				},
+				{
+					name: warn about failure to launch tests,
+					run: 'echo "::warning title=UNIT-TESTS::unit tests failed for win-scons"',
+					shell: bash,
+					if: '${{ hashFiles("build/test/passed") == "" }}'
+				}
 			]
 		},
 		# win-mingw: {