Update the ESLint dependencies, and also tweak the no-multiple-empty-lines rules

Since multiple empty lines is virtually unused in the code-base, and the few cases that do exist look like "typos", let's enforce greater consistency here; please see https://eslint.org/docs/rules/no-multiple-empty-lines.

src/core/cff_parser.js

@@ -96,7 +96,6 @@ var CFFStandardStrings = [
   'Black', 'Bold', 'Book', 'Light', 'Medium', 'Regular', 'Roman', 'Semibold'
 ];
 
-
 var CFFParser = (function CFFParserClosure() {
   var CharstringValidationData = [
     null,

src/core/evaluator.js

@@ -1351,7 +1351,6 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
           textContentItem.textRunBreakAllowed = false;
         }
 
-
         textContentItem.initialized = true;
         return textContentItem;
       }

src/core/font_renderer.js

@@ -676,7 +676,6 @@ var FontRendererFactory = (function FontRendererFactoryClosure() {
     },
   });
 
-
   return {
     create: function FontRendererFactory_create(font, seacAnalysisEnabled) {
       var data = new Uint8Array(font.data);