[libc++][CI] Removes clang-tidy references. (#89092)

The clang-tidy selection has been made automatic recently so this is not
longer needed.

Thanks to Louis for spotting this.

Author: mordante

.github/workflows/libcxx-build-and-test.yaml

@@ -61,20 +61,17 @@ jobs:
         ]
         cc: [  'clang-19' ]
         cxx: [ 'clang++-19' ]
-        clang_tidy: [ 'ON' ]
         include:
           - config: 'generic-gcc'
             cc: 'gcc-13'
             cxx: 'g++-13'
-            clang_tidy: 'OFF'
     steps:
       - uses: actions/checkout@v4
       - name: ${{ matrix.config }}.${{ matrix.cxx }}
         run: libcxx/utils/ci/run-buildbot ${{ matrix.config }}
         env:
           CC: ${{ matrix.cc }}
           CXX: ${{ matrix.cxx }}
-          ENABLE_CLANG_TIDY: ${{ matrix.clang_tidy }}
       - uses: actions/upload-artifact@26f96dfa697d77e81fd5907df203aa23a56210a8 # v4.3.0
         if: always()
         with:
@@ -102,28 +99,23 @@ jobs:
         ]
         cc: [ 'clang-19' ]
         cxx: [ 'clang++-19' ]
-        clang_tidy: [ 'ON' ]
         include:
           - config: 'generic-gcc-cxx11'
             cc: 'gcc-13'
             cxx: 'g++-13'
-            clang_tidy: 'OFF'
           - config: 'generic-cxx23'
             cc: 'clang-17'
             cxx: 'clang++-17'
-            clang_tidy: 'OFF'
           - config: 'generic-cxx26'
             cc: 'clang-18'
             cxx: 'clang++-18'
-            clang_tidy: 'ON'
     steps:
       - uses: actions/checkout@v4
       - name: ${{ matrix.config }}
         run: libcxx/utils/ci/run-buildbot ${{ matrix.config }}
         env:
           CC: ${{ matrix.cc }}
           CXX: ${{ matrix.cxx }}
-          ENABLE_CLANG_TIDY: ${{ matrix.clang_tidy }}
       - uses: actions/upload-artifact@26f96dfa697d77e81fd5907df203aa23a56210a8 # v4.3.0
         if: always()  # Upload artifacts even if the build or test suite fails
         with:
@@ -188,7 +180,6 @@ jobs:
         env:
           CC: clang-19
           CXX: clang++-19
-          ENABLE_CLANG_TIDY: "OFF"
       - uses: actions/upload-artifact@26f96dfa697d77e81fd5907df203aa23a56210a8 # v4.3.0
         if: always()
         with: