Fix parsing of document URLs with semicolons in them
Fix parsing of document URLs with semicolons in them

Some G5 document URLs (well, at least one) have semicolons in them, which confuses `urlparse`, which splits off anything after a semicolon into params.

By replacing the semicolons with their URL-encoded escape then the methods changed here work properly.

As the methods are only used for finding the document extension and extracting a 'nice' document title, we don't need to worry overly about making the substitution here as the change will not be propagated to any displayed links, etc.

AusDTO/dto-digitalmarketplace-buyer-frontend,alphagov/digitalmarketplace-buyer-frontend,alphagov/digitalmarketplace-buyer-frontend,AusDTO/dto-digitalmarketplace-buyer-frontend,alphagov/digitalmarketplace-buyer-frontend,AusDTO/dto-digitalmarketplace-buyer-frontend,alphagov/digitalmarketplace-buyer-frontend,AusDTO/dto-digitalmarketplace-buyer-frontend