Convert all source transform tests to use template strings.
Convert all source transform tests to use template strings.

decaffeinate/decaffeinate,decaffeinate/decaffeinate,eventualbuddha/decaffeinate,goatslacker/decaffeinate,alangpierce/decaffeinate,greyhwndz/decaffeinate,edi9999/decaffeinate,alangpierce/decaffeinate,netei/decaffeinate,lunks/decaffeinate,lunks/decaffeinate,alangpierce/decaffeinate,eventualbuddha/decaffeinate,netei/decaffeinate