Rename file to match generate-package-json.ts (#1232)

## Summary:

I'm creating this PR so I have a code change that can trigger a new release. 

Backstory: I thought I had published this package once already, but I hadn't. When I cut the v0.0.2 release it failed because the package does not exist on npmjs.com yet and can't be published without Trusted Publishing being enabled (the exact problem this tool is meant to help with). 

Since then, I've manually published a placeholder package and enabled Trusted Publishing on npmjs (https://www.npmjs.com/package/@khanacademy/wonder-stuff-tool-publish-new-pkg/access). 

When this PR is landed we can cut the release and it should publish successfully.

Issue: LEMS-3681

## Test plan:

Author: jeremywiebe

Reviewers: somewhatabstract

Required Reviewers:

Approved By: somewhatabstract

Checks: ✅ 7 checks were successful, ⏭️  1 check has been skipped

Pull Request URL: #1232

Author: jeremywiebe

.changeset/young-papers-joke.md

@@ -0,0 +1,5 @@
+---
+"@khanacademy/wonder-stuff-tool-publish-new-pkg": patch
+---
+
+Internal re-organization - no production changes

packages/wonder-stuff-tool-new-pkg/src/__tests__/write-package-files.test.ts

@@ -4,7 +4,7 @@ import fs from "node:fs";
 import {writePackageFiles} from "../write-package-files";
 
 import * as generatePackageJsonModule from "../generate-package-json";
-import * as generateReadmeModule from "../generate-readme.md";
+import * as generateReadmeModule from "../generate-readme-md";
 import * as generateIndexJSModule from "../generate-index-js";
 
 describe("#writePackageFiles", () => {

…f-tool-new-pkg/src/generate-readme.md.ts …f-tool-new-pkg/src/generate-readme-md.tspackages/wonder-stuff-tool-new-pkg/src/generate-readme.md.ts renamed to packages/wonder-stuff-tool-new-pkg/src/generate-readme-md.ts packages/wonder-stuff-tool-new-pkg/src/generate-readme.md.ts renamed to packages/wonder-stuff-tool-new-pkg/src/generate-readme-md.ts

@@ -1,7 +1,7 @@
 import {writeFile} from "node:fs/promises";
 import {join} from "node:path";
 import {generatePackageJson} from "./generate-package-json";
-import {generateReadme} from "./generate-readme.md";
+import {generateReadme} from "./generate-readme-md";
 import {generateIndexJs} from "./generate-index-js";
 
 /**