Fix DebuggerSetsVariablesWithConversion test which indicates bug

[andyleejordan]

I confirmed this is a real bug when reproducing manually. Setting variables with the preview's debugger can fail if they need to be converted. Left a note actually where it throws the exception.

PowerShellEditorServices/test/PowerShellEditorServices.Test/Debugging/DebugServiceTests.cs

Lines 616 to 672 in 20a3516

	[Fact(Skip = "Variable conversion is broken")]
	public async Task DebuggerSetsVariablesWithConversion()
	{
	await debugService.SetLineBreakpointsAsync(
	variableScriptFile,
	new[] { BreakpointDetails.Create(variableScriptFile.FilePath, 14) }).ConfigureAwait(true);
	// Execute the script and wait for the breakpoint to be hit
	Task _ = ExecuteVariableScriptFile();
	AssertDebuggerStopped(variableScriptFile.FilePath);
	VariableScope[] scopes = debugService.GetVariableScopes(0);
	VariableDetailsBase[] variables = GetVariables(VariableContainerDetails.LocalScopeName);
	// Test set of a local string variable (not strongly typed but force conversion)
	const string newStrValue = "False";
	const string newStrExpr = "$false";
	VariableScope localScope = Array.Find(scopes, s => s.Name == VariableContainerDetails.LocalScopeName);
	string setStrValue = await debugService.SetVariableAsync(localScope.Id, "$strVar2", newStrExpr).ConfigureAwait(true);
	Assert.Equal(newStrValue, setStrValue);
	// Test set of script scope bool variable (strongly typed)
	VariableScope scriptScope = Array.Find(scopes, s => s.Name == VariableContainerDetails.ScriptScopeName);
	const string newBoolValue = "$true";
	const string newBoolExpr = "1";
	string setBoolValue = await debugService.SetVariableAsync(scriptScope.Id, "$scriptBool", newBoolExpr).ConfigureAwait(true);
	Assert.Equal(newBoolValue, setBoolValue);
	// Test set of global scope ActionPreference variable (strongly typed)
	VariableScope globalScope = Array.Find(scopes, s => s.Name == VariableContainerDetails.GlobalScopeName);
	const string newGlobalValue = "Continue";
	const string newGlobalExpr = "'Continue'";
	string setGlobalValue = await debugService.SetVariableAsync(globalScope.Id, "$VerbosePreference", newGlobalExpr).ConfigureAwait(true);
	Assert.Equal(newGlobalValue, setGlobalValue);
	// The above just tests that the debug service returns the correct new value string.
	// Let's step the debugger and make sure the values got set to the new values.
	await Task.Run(() => debugService.StepOver()).ConfigureAwait(true);
	AssertDebuggerStopped(variableScriptFile.FilePath);
	// Test set of a local string variable (not strongly typed but force conversion)
	variables = GetVariables(VariableContainerDetails.LocalScopeName);
	var strVar = Array.Find(variables, v => v.Name == "$strVar2");
	Assert.Equal(newStrValue, strVar.ValueString);
	scopes = debugService.GetVariableScopes(0);
	// Test set of script scope bool variable (strongly typed)
	variables = GetVariables(VariableContainerDetails.ScriptScopeName);
	var boolVar = Array.Find(variables, v => v.Name == "$scriptBool");
	Assert.Equal(newBoolValue, boolVar.ValueString);
	// Test set of global scope ActionPreference variable (strongly typed)
	variables = GetVariables(VariableContainerDetails.GlobalScopeName);
	var globalVar = Array.Find(variables, v => v.Name == "$VerbosePreference");
	Assert.Equal(newGlobalValue, globalVar.ValueString);
	}