GitHub workflows: Migrate to `turtlesec-no/get-ninja`

This does not depend on the deprecated Node.js v12.

PiperOrigin-RevId: 538672875
Change-Id: Ie26e3adfc67626d53ad5a3d12d48099efd4fe827

.github/workflows/ubuntu-cmake-contrib.yml

@@ -50,7 +50,7 @@ jobs:
           ${{github.workspace}}/build/_deps/${{matrix.contrib}}-*/**
 
     - name: Install ninja-build tool
-      uses: seanmiddleditch/gha-setup-ninja@v3
+      uses: turtlesec-no/get-ninja@1.1.0
 
     - name: Install/configure Clang compiler toolchain
       if: matrix.compiler == 'clang'

.github/workflows/ubuntu-cmake.yml

@@ -82,7 +82,7 @@ jobs:
           ${{github.workspace}}/build/_deps
 
     - name: Install ninja-build tool
-      uses: seanmiddleditch/gha-setup-ninja@v3
+      uses: turtlesec-no/get-ninja@1.1.0
 
     - name: Install/configure Clang compiler toolchain
       if: matrix.compiler == 'clang'