ci(musl): only run on rust file changes (#676)

Author: George-Miao

.github/workflows/ci_test_musl.yml

@@ -4,9 +4,17 @@ on:
   push:
     branches:
       - master
+    paths:
+      - '**/*.rs'
+      - '**/Cargo.toml'
+      - '.github/workflows/ci_test_musl.yml'
   pull_request:
     branches:
       - master
+    paths:
+      - '**/*.rs'
+      - '**/Cargo.toml'
+      - '.github/workflows/ci_test_musl.yml'
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}-${{ github.event_name }}
@@ -45,4 +53,4 @@ jobs:
               ARGS+=("--target" "${{ matrix.setup.target }}")
           fi
 
-          cross test --workspace "${ARGS[@]}"
+          cross test --workspace "${ARGS[@]}"