test(config): add test for consistent config (#4215)

.github/copilot-instructions.md

@@ -0,0 +1,8 @@
+On Windows we use msys2 and ucrt64 to compile.
+You need to prefix commands with `C:\msys64\msys2_shell.cmd -defterm -here -no-start -ucrt64 -c`.
+
+Prefix build directories with `cmake-build-`.
+
+The test executable is named `test_sunshine`
+
+Always follow the style guidelines defined in .clang-format for c/c++ code.