translation validation tests allow errors with "%1"-type inputs to go through #137
Description
There have been several types of error in the Transifex->Scratch Editor->blocks translations, which the validation tests in scratch-l10n currently do not catch.
We should Add functionality to the validate-extension-inputs.js script so it can check for the presence of the correct inputs of the form "/%d+/".
Examples of manual fixes we've had to detect and make:
