ci: remove `stable` toolchain from ci

.github/workflows/build.yml

@@ -45,7 +45,6 @@ jobs:
       fail-fast: false
       matrix:
         build:
-          - stable
           - nightly-gnu
           - nightly-musl
           - nightly-32
@@ -54,9 +53,6 @@ jobs:
           - win-msvc
           - win-gnu
         include:
-          - build: stable
-            os: ubuntu-22.04
-            rust: stable
           - build: nightly-gnu
             os: ubuntu-22.04
             rust: nightly

Cargo.toml

@@ -23,4 +23,4 @@ webbrowser = { version = '0.8.2' }
 
 [dev-dependencies]
 test-case = { version = '3.1.0' }
-mockall = { version = '0.11.4' }
+mockall = { version = '0.11.4', features = ["nightly"] }

rust-toolchain.toml

@@ -0,0 +1,3 @@
+[toolchain]
+channel = "nightly"
+profile = "default"