Clean up my-ts-node.js (#2031)

## Checklist

- [-] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [-] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [-] I have not broken the cheatsheet

Author: pokey

packages/common/scripts/my-ts-node.js

@@ -37,9 +37,9 @@ function createTempDirectory(baseDir) {
     "my-ts-node-tmp",
     randomBytes(16).toString("hex"),
   );
-  if (!existsSync(tempDir)) {
-    mkdirSync(tempDir, { recursive: true });
-  }
+
+  mkdirSync(tempDir, { recursive: true });
+
   return tempDir;
 }