[v2] Report full error for schema violations

[mikeharder]

When reporting schema violations, I think we should include the full dump of the error object, not just the message.

autorest/src/autorest-core/lib/pipeline/schema-validation.ts

Lines 25 to 33 in 6a1a091

	for (const error of errors) {
	config.Message({
	Channel: Channel.Error,
	Details: error,
	Plugin: "schema-validator",
	Source: [{ document: fileIn.key, Position: { path: parseJsonPointer(error.path) } as any }],
	Text: `Schema violation: ${error.message}`
	});
	}

Replace error.message with something like JSON.stringify(error).