Parser doesn't take into account bold format in notes

[davorpa]

Having current code:

free-programming-books-parser/index.js

Lines 140 to 172 in dc53b8c

	} else {
	// for now we assume that all previous ifs are mutually exclusive with this, may polish later
	if (i.type === "emphasis") {
	// this is the emphasis, add it in boldface and move on
	s += "*" + i.children[0].value + "*";
	} else if (i.type === "link") {
	// something has gone terribly wrong. this book must be viewed and edited manually.
	entry.manualReviewRequired = true;
	break;
	} else {
	// hopefully this is the end of the note
	let rightParen = i.value.indexOf(")");
	if (rightParen === -1) {
	// we have to go AGAIN
	s += i.value;
	} else {
	// finally, we have reached the end of the note
	entry.notes.push(stripParens(s + i.value.slice(0, rightParen + 1)));
	s = "";
	// this is a copypaste of another block of code. probably not a good thing tbh.
	leftParen = i.value.indexOf("(");
	while (leftParen != -1) {
	rightParen = i.value.indexOf(")", leftParen);
	if (rightParen === -1) {
	// there must be some *emphasis* found
	s += i.value.slice(leftParen);
	break;
	}
	entry.notes.push(i.value.slice(leftParen + 1, rightParen));
	leftParen = i.value.indexOf("(", rightParen);
	}
	}
	}

If a bold format is found, the i.value is undefined and then the program crash. It should check if i.type == "strong" or have i.children.

Resources affected:

• https://github.com/EbookFoundation/free-programming-books/blob/fc4b0c5c139b952de979aa54a4de5141ea280906/books/free-programming-books-fr.md?plain=1#L73

In general, we should extends the fix in depth to other inline formats like emphasis (already exists), bold, code, image...