test: add unit test for inkscape.ts

src/converters/graphicsmagick.ts

@@ -315,7 +315,7 @@ export function convert(
   convertTo: string,
   targetPath: string,
   options?: unknown,
-  execFile: ExecFileFn = execFileOriginal,
+  execFile: ExecFileFn = execFileOriginal, // to make it mockable
 ): Promise<string> {
   return new Promise((resolve, reject) => {
     execFile("gm", ["convert", filePath, targetPath], (error, stdout, stderr) => {