`mlx-ui` logs show session error messages

**Describe the bug**

The logs of the MLX UI show error messages like these:

```
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/DVYkJydSnkjCT8jamfyVB9DWjCDFF0W6.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/DVYkJydSnkjCT8jamfyVB9DWjCDFF0W6.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/DVYkJydSnkjCT8jamfyVB9DWjCDFF0W6.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/DVYkJydSnkjCT8jamfyVB9DWjCDFF0W6.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/DVYkJydSnkjCT8jamfyVB9DWjCDFF0W6.json'
```

**Steps to Reproduce**

Deploy MLX and open the MLX web UI while tailing the logs of the `mlx-ui` pod/container.

**Logs:**

```Shell
$ kubectl -n kubeflow logs -f mlx-ui-755456f99-4bpfh

> aiops-frontend@0.1.0 build
> react-scripts build

Creating an optimized production build...
Compiled successfully.

File sizes after gzip:

343.26 KB build/static/js/2.d6682b1c.chunk.js
62.85 KB build/static/js/main.4d6ec1c7.chunk.js
3.84 KB build/static/css/main.265e3da4.chunk.css
2.72 KB build/static/css/2.21151bd0.chunk.css
780 B build/static/js/runtime-main.b8b6e910.js

The project was built assuming it is hosted at ./.
You can control this with the homepage field in your package.json.

The build folder is ready to be deployed.

Find out more about deployment here:

bit.ly/CRA-deploy

npm notice
npm notice New minor version of npm available! 8.11.0 -> 8.13.0
npm notice Changelog:
npm notice Run `npm install -g npm@8.13.0` to update!
npm notice
[HPM] Proxy created: / -> http://mlx-api
Server listening at http://localhost:3000
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
[session-file-store] will retry, error on last attempt: Error: ENOENT: no such file or directory, open 'sessions/JILS35zOlw0Nz35p2aL4pOYTD_5XlpPv.json'
```

This could be related to [recent changes (#339)](https://github.com/machine-learning-exchange/mlx/pull/339/files#diff-2c9ac92c5af29ab8320055fb3298f370e0cd355186103a8ac46220c36be12bdeR25-R26) in the mlx-ui container image to run as non-root user:

Also see:
- https://github.com/valery-barysok/session-file-store/issues/26#issuecomment-278110944
> fix it by `chmod +x sessions`
- https://github.com/valery-barysok/session-file-store/issues/26#issuecomment-192769005
> `res.clearCookie(options.name);` ... works like a charm