Update clang format workflow

Author: lgulich

.github/workflows/clang_format.yml

@@ -10,7 +10,7 @@ jobs:
     - uses: actions/checkout@v2
     - uses: DoozyX/[email protected]
       with:
-        source: 'include/ src/ test/'
+        source: 'include/ test/'
         exclude: ''
         extensions: 'h,cpp,c,cc'
         clangFormatVersion: 12