bump rust to 1.81 (#1458)

To be able to work with reth at the rpc level and don't have any rust
conflicting version, we should rely on last stable (1.81), as per the
minimal supported version of reth:

https://github.com/paradigmxyz/reth/blob/e2f35ce6df14bb67c19f4f1f7e8f6dde6f1bdffd/Cargo.toml#L4

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.github/workflows/ci.yml

@@ -24,6 +24,7 @@ jobs:
       solidity: ${{ steps.filter.outputs.solidity }}
       tests: ${{ steps.filter.outputs.tests }}
       makefile: ${{ steps.filter.outputs.makefile }}
+      rust: ${{ steps.filter.outputs.rust }}
     steps:
       - uses: actions/checkout@v4
       - uses: dorny/paths-filter@v3
@@ -40,14 +41,17 @@ jobs:
               - 'tests/**'
             makefile:
               - 'Makefile'
+            rust:
+              - 'rust-toolchain'
 
   build:
     runs-on: ubuntu-latest
     needs: paths-filter
     if:
       needs.paths-filter.outputs.src == 'true' ||
       needs.paths-filter.outputs.kakarot_scripts == 'true' ||
-      needs.paths-filter.outputs.makefile == 'true'
+      needs.paths-filter.outputs.makefile == 'true' ||
+      needs.paths-filter.outputs.rust == 'true'
     steps:
       - uses: actions/checkout@v4
       - uses: astral-sh/setup-uv@v2
@@ -110,7 +114,8 @@ jobs:
       needs.paths-filter.outputs.kakarot_scripts == 'true' ||
       needs.paths-filter.outputs.solidity == 'true' ||
       needs.paths-filter.outputs.tests == 'true' ||
-      needs.paths-filter.outputs.makefile == 'true'
+      needs.paths-filter.outputs.makefile == 'true' ||
+      needs.paths-filter.outputs.rust == 'true'
     steps:
       - uses: actions/checkout@v4
       - name: Extract Katana Version

rust-toolchain

@@ -1 +1 @@
-1.80.0
+1.81.0