feat: remove our dependency on undici (#442)

package.json

@@ -19,7 +19,7 @@
     "./package.json": "./package.json"
   },
   "engines": {
-    "node": ">=18"
+    "node": ">=18.13.0"
   },
   "files": [
     "dist"
@@ -47,8 +47,7 @@
   "homepage": "https://github.com/readmeio/fetch-har#readme",
   "dependencies": {
     "@readme/data-urls": "^3.0.0",
-    "@types/har-format": "^1.2.13",
-    "undici": "^5.25.1"
+    "@types/har-format": "^1.2.13"
   },
   "devDependencies": {
     "@jsdevtools/host-environment": "^2.1.2",

src/index.ts

@@ -60,11 +60,9 @@ export default async function fetchHAR(har: Har, opts: FetchHAROptions = {}): Pr
 
   if (!globalThis.File) {
     try {
-      // Node's native `fetch` implementation unfortunately does not make this API global so we need
-      // to pull it in if we don't have it.
-      const UndiciFile = (await import('undici')).File;
+      const NodeFile = (await import('node:buffer')).File;
       // @ts-expect-error the types don't match exactly, which is expected!
-      globalThis.File = UndiciFile;
+      globalThis.File = NodeFile;
     } catch (e) {
       throw new Error(
         'The File API is required for this library. https://developer.mozilla.org/en-US/docs/Web/API/File',