workflows/release-binaries: Drop install-ninja action (llvm#167070)

ninja is already installed by default on Linux and macOS.

Author: tstellar

.github/workflows/release-binaries.yml

@@ -188,9 +188,6 @@ jobs:
       with:
         ref: ${{ needs.prepare.outputs.ref }}
 
-    - name: Install Ninja
-      uses: llvm/actions/install-ninja@5dd955034a6742a2e21d82bf165fcb1050ae7b49 # main
-
     - name: Set Build Prefix
       id: setup-stage
       shell: bash