fix wrong casting with into filesize (#13110)

# Description
Fix wrong casting which is related to
https://github.com/nushell/nushell/pull/12974#discussion_r1618598336

# User-Facing Changes
AS-IS (before fixing)
```
$ "-10000PiB" | into filesize
6.2 EiB                                                         <--- Wrong casted value
$ "10000PiB" | into filesize 
-6.2 EiB                                                        <--- Wrong casted value
```

TO-BE (after fixing)
```
$ "-10000PiB" | into filesize
Error: nu:🐚:cant_convert

  × Can't convert to filesize.
   ╭─[entry #6:1:1]
 1 │ "-10000PiB" | into filesize
   · ─────┬─────
   ·      ╰── can't convert string to filesize
   ╰────

$ "10000PiB" | into filesize
Error: nu:🐚:cant_convert

  × Can't convert to filesize.
   ╭─[entry #7:1:1]
 1 │ "10000PiB" | into filesize
   · ─────┬────
   ·      ╰── can't convert string to filesize
   ╰────
```

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

@@ -76,6 +76,13 @@ fn into_filesize_wrong_negative_str_filesize() {
     assert!(actual.err.contains("can't convert string to filesize"));
 }
 
+#[test]
+fn into_filesize_large_negative_str_filesize() {
+    let actual = nu!("'-10000PiB' | into filesize");
+
+    assert!(actual.err.contains("can't convert string to filesize"));
+}
+
 #[test]
 fn into_filesize_negative_str() {
     let actual = nu!("'-1' | into filesize");
@@ -104,6 +111,13 @@ fn into_filesize_wrong_positive_str_filesize() {
     assert!(actual.err.contains("can't convert string to filesize"));
 }
 
+#[test]
+fn into_filesize_large_positive_str_filesize() {
+    let actual = nu!("'+10000PiB' | into filesize");
+
+    assert!(actual.err.contains("can't convert string to filesize"));
+}
+
 #[test]
 fn into_filesize_positive_str() {
     let actual = nu!("'+1' | into filesize");