Recognize file name in reference fragment in getPDFFileNameFromURL
Recognize file name in reference fragment in getPDFFileNameFromURL

The regular expression incorrectly marked a group as capturing.
For `http://example.com/#file.pdf`, the expected result is "file.pdf",
but instead "document.pdf" was returned.

xavier114fch/pdf.js,mainegreen/pdf.js,showpad/mozilla-pdf.js,nawawi/pdf.js,tinderboxhq/pdf.js,1and1/pdf.js,macroplant/pdf.js,skalnik/pdf.js,mukulmishra18/pdf.js,adlerweb/pdf.js-Touch,timvandermeij/pdf.js,caremerge/pdf.js,websirnik/pdf.js,jasonjensen/pdf.js,mozilla/pdf.js,websirnik/pdf.js,yurydelendik/pdf.js,Snuffleupagus/pdf.js,Snuffleupagus/pdf.js,Snuffleupagus/pdf.js,xavier114fch/pdf.js,showpad/mozilla-pdf.js,nawawi/pdf.js,timvandermeij/pdf.js,Shoobx/pdf.js,mukulmishra18/pdf.js,Rob--W/pdf.js,WhitesteinTechnologies/wt-vaadin-pdf.js,timvandermeij/pdf.js,showpad/mozilla-pdf.js,Shoobx/pdf.js,nawawi/pdf.js,Shoobx/pdf.js,adlerweb/pdf.js-Touch,mozilla/pdf.js,ydfzgyj/pdf.js,mysterlune/pdf.js,caremerge/pdf.js,Rob--W/pdf.js,ydfzgyj/pdf.js,jasonjensen/pdf.js,macroplant/pdf.js,1and1/pdf.js,yurydelendik/pdf.js,mainegreen/pdf.js,mysterlune/pdf.js,macroplant/pdf.js,skalnik/pdf.js,tinderboxhq/pdf.js,mozilla/pdf.js,WhitesteinTechnologies/wt-vaadin-pdf.js