build_docker_image.sh fails to work on arm64

**Error Message:**

```
#13 0.281 /tmp/clang-build/build /
#13 0.281 Running build
#13 0.296 CMake Error at CMakeLists.txt:46 (project):
#13 0.296 Running
#13 0.296
#13 0.296 '/usr/local/bin/ninja' '--version'
#13 0.296
#13 0.296 failed with:
#13 0.296
#13 0.296 /usr/local/bin/ninja: 1: Syntax error: "(" unexpected
#13 0.296
#13 0.296
#13 0.296
#13 0.296 CMake Error: CMAKE_C_COMPILER not set, after EnableLanguage
#13 0.296 CMake Error: CMAKE_CXX_COMPILER not set, after EnableLanguage
#13 0.296 CMake Error: CMAKE_ASM_COMPILER not set, after EnableLanguage
#13 0.297 -- Configuring incomplete, errors occurred!
```

**Exact location in the code:**

lvm/utils/docker/debian12/Dockerfile

```
RUN wget "https://github.com/ninja-build/ninja/releases/download/v1.12.1/ninja-linux.zip" && \
echo "6f98805688d19672bd699fbbfa2c2cf0fc054ac3df1f0e6a47664d963d530255 ninja-linux.zip" \
| sha256sum -c && \
unzip ninja-linux.zip -d /usr/local/bin && \
rm ninja-linux.zip
```

Start with the shown download-and-unzip RUN block in lvm/utils/docker/debian12/Dockerfile and reproduce the Docker image build on arm64. Check why the downloaded Ninja executable cannot be run, then verify that CMake can invoke Ninja and configure the LLVM build without the reported errors.

Written by the indexing model from the issue text.