Fix negative value file size for "into filesize" (issue #12396) (#12443)

# Description
Add support for using negative values file size for `into filesize`.
This will help in sorting the file size if negative values are also
passed.

**Before**

![image](https://github.com/nushell/nushell/assets/43441496/e115b4b3-7526-4379-8dc0-f4f4e44839a1)
**After**

![image](https://github.com/nushell/nushell/assets/43441496/4a75fb40-ebe6-46eb-b9d2-55f37db7a6fa)

# User-Facing Changes
- User can now sort negative filesize also

# Tests + Formatting
- 🟢 toolkit fmt
- 🟢 toolkit clippy
- 🟢 toolkit test
- 🟢 toolkit test stdlib

# After Submitting

---------

Co-authored-by: Priyank Singh <priyank.singh@soroco.com>

crates/nu-command/tests/commands/into_filesize.rs

@@ -61,3 +61,10 @@ fn into_filesize_negative_filesize() {
 
     assert!(actual.out.contains("-3.0 KiB"));
 }
+
+#[test]
+fn into_negative_filesize() {
+    let actual = nu!("'-1' | into filesize");
+
+    assert!(actual.out.contains("-1 B"));
+}