[Validator] Fix Binary Format when maxSize is smaller than uploadLimit

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | NA
| License       | MIT
| Doc PR        | NA

Add a small fix to #12103.
If constraint `maxSize` is defined with base10 (K or M) and is smaller than ini `upload_max_filesize` (defined with base2 (Ki, Mi, Gi, ...) then the error message will not be correctly displayed.