fix: issue #373: handle bad encoding expcetion by start page renderin…

[modesty]

…g after page operator list is resolved, add i373_err_broken.pdf to verify

to verify:

1. npm run test and npm run test:forms should all pass
2. npm run test:misc should see list of success and error and total counter matches expected
3. npm run test:e will parse i373_err_broken.pdf only, exception should be handled gracefully