Use stable on CI so it's always using the 'right' version.

That way it avoids to download the toolchain on each CI run.

Author: Byron

.github/workflows/publish.yaml

@@ -1,4 +1,6 @@
 name: 'Publish'
+env:
+  RUSTUP_TOOLCHAIN: stable
 on:
   schedule:
     # every day at 3am

.github/workflows/push.yaml

@@ -7,6 +7,7 @@ on:
 
 env:
   RUST_BACKTRACE: full
+  RUSTUP_TOOLCHAIN: stable
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -169,7 +170,9 @@ jobs:
         env:
           GITBUTLER_TESTS_NO_CLEANUP: '1'
         name: cargo test
-      - run: cargo clippy --workspace --all-targets -- -D warnings
+      - run: |
+          rustup component add clippy
+          cargo clippy --workspace --all-targets -- -D warnings
         name: cargo clippy
       - run: |
           set -e

.github/workflows/test-e2e-blackbox.yml

@@ -1,4 +1,6 @@
 name: E2E Blackbox Tests
+env:
+  RUSTUP_TOOLCHAIN: stable
 on:
   pull_request:
     branches: [master]