Fix the impl for Displaying zero element in Fp (arkworks-rs#806)

* Fix the impl for `Display`ing zero element in Fp

* Update changelog

---------

Co-authored-by: Marcin <marcin.gorny.94@protonmail.com>

CHANGELOG.md

@@ -44,6 +44,7 @@
 
 - [\#747](https://github.com/arkworks-rs/algebra/pull/747) (`ark-ff-macros`) Fix fetching attributes in `MontConfig` macro.
 - [\#803](https://github.com/arkworks-rs/algebra/pull/803) (`ark-ec`, `ark-test-template`) Fix incorrect decomposition in GLV.
+- [\#806](https://github.com/arkworks-rs/algebra/pull/806) (`ark-ff`) Fix the impl for `Display`ing zero element in Fp.
 
 ## v0.4.2
 

ff/src/fields/models/fp/mod.rs

@@ -676,7 +676,7 @@ impl<P: FpConfig<N>, const N: usize> Display for Fp<P, N> {
     #[inline]
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
         let string = self.into_bigint().to_string();
-        write!(f, "{}", string.trim_start_matches('0'))
+        write!(f, "{}", string)
     }
 }