Fix expected schema output

Author: spawnia

src/utilities/__tests__/printSchema-test.ts

@@ -795,7 +795,9 @@ describe('Type System Printer', () => {
         url: String!
       ) on SCALAR
 
-      """Indicates that exactly one field must be supplied and that field must not be \`null\`."""
+      """
+      Indicates that exactly one field must be supplied and that field must not be \`null\`.
+      """
       directive @oneOf on INPUT_OBJECT
 
       """