Reorder `guess_sourcemap_reference` guesses

Per the [source map format specification](https://tc39.es/ecma426/#sec-source-map-naming), we should reorder the guesses we make in [`guess_sourcemap_reference`](https://github.com/getsentry/sentry-cli/blob/5217470c0244b5dc44495f1ddd8c7f4171118a58/src/utils/sourcemaps.rs#L109) to first guess `foo.min.js -> foo.min.js.map`, as this is the default naming convention for sourcemaps.