[FIX] base,tools: raise usererror instead of a valueerror

This issue is generated when the user uploads an image of more than
50.0 million pixels, so error would be generated. But, currently it raises a
`ValueError` which results in traceback. So, we replace it with
`UserError` so the user has an idea about Image size or pixel being excessive.

closes odoo/odoo#120900

Sentry: - 4075426049
X-original-commit: 59a3f75b
Signed-off-by: Rémy Voet <ryv@odoo.com>