chore: code clean-up

PDFMergerBase.js

@@ -163,7 +163,7 @@ export default class PDFMergerBase {
     // see https://developer.mozilla.org/en-US/docs/Web/API/URL
     if (input instanceof URL) {
       if (typeof fetch === 'undefined') {
-        throw new Error('fetch is not defined. You need to use a polyfill for this to work in Node.js.')
+        throw new Error('fetch is not defined. You need to use a polyfill for this to work.')
       }
       const res = await fetch(input)
       const aBuffer = await res.arrayBuffer()

README.md

@@ -4,8 +4,7 @@ This node.js library can **merge multiple PDF documents**, or parts of them, to
 
 ## Legacy notes
 
-* If you are searching for the legacy version based on 
-[pdfjs](https://www.npmjs.com/package/pdfjs) please install a [v3 release](https://github.com/nbesli/pdf-merger-js/releases?q=v3&expanded=true). Since [v4](https://github.com/nbesli/pdf-merger-js/releases?q=v4&expanded=true) we use [pdf-lib](https://pdf-lib.js.org/) instead.
+* If you are searching for the legacy version based on [pdfjs](https://www.npmjs.com/package/pdfjs) please install a [v3 release](https://github.com/nbesli/pdf-merger-js/releases?q=v3&expanded=true). Since [v4](https://github.com/nbesli/pdf-merger-js/releases?q=v4&expanded=true) we use [pdf-lib](https://pdf-lib.js.org/) instead.
 * If you are searching for a legacy version using CommonJS modules please install a [v4 release](https://github.com/nbesli/pdf-merger-js/releases?q=v4&expanded=true). Since [v5](https://github.com/nbesli/pdf-merger-js/releases?q=v5&expanded=true) we use the modern ESM ("import") instead of the CommonJS ("require) module standard.
 
 This library is inspired by the [PHP library PDFMerger](https://github.com/myokyawhtun/PDFMerger) and has a very similar API.
@@ -14,15 +13,15 @@ This library is inspired by the [PHP library PDFMerger](https://github.com/myoky
 
 `npm install --save pdf-merger-js`
 
-of global installation if you want to use the cli tool:
+or global installation if you just want to use the cli tool:
 
 `npm install -g pdf-merger-js`
 
 ## Usage
 
 ### CLI
 
-```
+```txt
 Options:
   -V, --version              output the version number
   -o, --output <outputFile>  Merged PDF output file path

test/PDFMerger.test.js

@@ -124,10 +124,10 @@ describe('PDFMerger', () => {
     const testIfFetch = typeof fetch !== 'undefined' ? test : test.skip
     testIfFetch('provide input as URL', async () => {
       const merger = new PDFMerger()
-      const TestfileAURL = new URL('https://raw.githubusercontent.com/nbesli/pdf-merger-js/master/test/fixtures/Testfile_A.pdf')
+      const TestfileAURL = new URL('https://github.com/nbesli/pdf-merger-js/raw/master/test/fixtures/Testfile_A.pdf')
       expect(TestfileAURL).toBeInstanceOf(URL)
       await merger.add(TestfileAURL)
-      const TestfileBURL = new URL('https://raw.githubusercontent.com/nbesli/pdf-merger-js/master/test/fixtures/Testfile_B.pdf')
+      const TestfileBURL = new URL('https://github.com/nbesli/pdf-merger-js/raw/master/test/fixtures/Testfile_B.pdf')
       expect(TestfileBURL).toBeInstanceOf(URL)
       await merger.add(TestfileBURL)
       const diff = await pdfDiff(