chore:: Refactor field tests to use pasta_curves instead of blstrs

- Follow-up of lurk-lab#774
- Swapped out `blstrs::Scalar` implementation in `src/field.rs` with pasta_curves::pallas::Scalar
- Readjusted tests to now run on the `pasta_curve` as opposed to the `blstrs`
- Updated `Cargo.toml` by removing `blstrs` from both the workspace and dev dependencies
- Removed the association of `blstrs/portable` from the `portable` feature in `Cargo.toml`

Cargo.toml

@@ -19,7 +19,6 @@ base-x = "0.2.11"
 bellpepper = { workspace = true }
 bellpepper-core = { workspace = true }
 bincode = { workspace = true }
-blstrs = { workspace = true }
 bytecount = "=0.6.4"
 camino = { workspace = true, features = ["serde1"] }
 clap = { workspace = true, features = ["derive"] }
@@ -93,7 +92,7 @@ default = []
 opencl = ["neptune/opencl", "nova/opencl"]
 cuda = ["neptune/cuda", "nova/cuda"]
 # compile without ISA extensions
-portable = ["blstrs/portable", "pasta-msm/portable", "nova/portable"]
+portable = ["pasta-msm/portable", "nova/portable"]
 flamegraph = ["pprof/flamegraph", "pprof/criterion"]
 
 [dev-dependencies]
@@ -123,7 +122,6 @@ base64 = "0.13.1"
 bellpepper = { git = "https://github.com/lurk-lab/bellpepper", branch = "dev" }
 bellpepper-core = { git = "https://github.com/lurk-lab/bellpepper", branch = "dev" }
 bincode = "1.3.3"
-blstrs = { git = "https://github.com/lurk-lab/blstrs", branch = "dev" }
 clap = "4.3.17"
 ff = "0.13"
 metrics = "0.21.1"

src/field.rs

@@ -263,10 +263,6 @@ pub trait LurkField: PrimeField + PrimeFieldBits {
     }
 }
 
-impl LurkField for blstrs::Scalar {
-    const FIELD: LanguageField = LanguageField::BLS12_381;
-}
-
 impl LurkField for pasta_curves::pallas::Scalar {
     const FIELD: LanguageField = LanguageField::Pallas;
 }
@@ -348,7 +344,7 @@ impl<'de, F: LurkField> Deserialize<'de> for FWrap<F> {
 #[cfg(test)]
 pub mod tests {
     use crate::z_data::{from_z_data, to_z_data};
-    use blstrs::Scalar as Fr;
+    use pasta_curves::pallas::Scalar as Fr;
     use pasta_curves::{pallas, vesta};
 
     use super::*;
@@ -473,7 +469,7 @@ pub mod tests {
 
         #[test]
         fn prop_bls_tag_roundtrip(x in any::<u64>()){
-            let f1 = blstrs::Scalar::from(x);
+            let f1 = pasta_curves::pallas::Scalar::from(x);
             let bytes = f1.to_repr().as_ref().to_vec();
             let mut bytes_from_u64 = [0u8; 32];
             bytes_from_u64[..8].copy_from_slice(&x.to_le_bytes());