change workflows to fix CI

Author: Prabhat1308

Diff for: .github/workflows/prod.yml

@@ -22,18 +22,18 @@ jobs:
           - uses: actions/checkout@v2
           - name: Install protobuf-compiler
             run: sudo apt-get update && sudo apt-get install -y protobuf-compiler
-          - run: rustup toolchain install ${{ matrix.rust }} && rustup default ${{ matrix.rust }} && rustup update ${{ matrix.rust }}
-          - name: Install Clippy
-            run: rustup component add clippy
-          - name: Install Rustfmt
-            run: rustup component add rustfmt
+          - name: Install Rust
+            uses: actions-rs/toolchain@v1
+            with:
+              profile: minimal
+              toolchain: ${{ matrix.rust }}
+              override: true
+              components: rustfmt, clippy
           - name: Build
             run: cargo build --release --verbose --features arkworks
           - name: Test
             run: cargo test --release --verbose --features arkworks
           - name: Lint
-            run: cargo clippy  --release --features arkworks 
+            run: cargo clippy --release --features arkworks 
           - name: Format
             run: cargo fmt -- --check
-
-        

Diff for: rustfmt.toml

@@ -0,0 +1,2 @@
+use_small_heuristics = "Max"
+imports_granularity = "Crate"