Remove our Web Worker workaround

[chasenlehara]

stealjs/steal-tools#775 was fixed so we can remove this workaround:

bit-docs-html-canjs/build-search-worker.js

Lines 33 to 43 in 0f11ce1

	}).then(function(){
	// Work around for https://github.com/stealjs/steal-tools/issues/775
	console.info('Replacing "window" with "self"');
	fs.readFile(dest, 'utf8', function(err, file){
	if(err) return console.error(err);
	file = file.replace(/window/gmi, 'self');
	fs.writeFile(dest, file, function(err){
	if(err) return console.error(err);
	console.info('Done');
	});
	});

I think all of those lines can be removed; we don’t have to read the file, modify it, and write it back out to disk.