[Docker] fix Almalinux 8 wrong default Python3 (triton-lang#6872)

Author: makslevental

.github/workflows/llvm-build.yml

@@ -9,6 +9,8 @@ on:
   pull_request:
     paths:
       - .github/workflows/llvm-build.yml
+      - .github/workflows/llvm-build/almalinux.Dockerfile
+      - .github/workflows/llvm-build/centos.Dockerfile
   workflow_dispatch:
 
 env:

.github/workflows/llvm-build/almalinux.Dockerfile

@@ -1,4 +1,5 @@
-FROM almalinux:8
+# https://github.com/AlmaLinux/container-images/blob/9f9b3c8c8cf4a57fd42f362570ff47c75788031f/default/amd64/Dockerfile
+FROM almalinux:8.10-20250411
 ARG llvm_dir=llvm-project
 # Add the cache artifacts and the LLVM source tree to the container
 ADD sccache /sccache
@@ -8,6 +9,7 @@ ENV SCCACHE_CACHE_SIZE="2G"
 
 RUN dnf install --assumeyes llvm-toolset
 RUN dnf install --assumeyes python38-pip python38-devel git
+RUN alternatives --set python3 /usr/bin/python3.8
 
 RUN python3 -m pip install --upgrade pip
 RUN python3 -m pip install --upgrade cmake ninja sccache lit
@@ -26,6 +28,8 @@ RUN cmake -GNinja -Bbuild \
   -DCMAKE_CXX_FLAGS="-Wno-everything" \
   -DCMAKE_LINKER=lld \
   -DCMAKE_INSTALL_PREFIX="/install" \
+  -DPython3_EXECUTABLE="/usr/bin/python3.8" \
+  -DPython_EXECUTABLE="/usr/bin/python3.8" \
   -DLLVM_BUILD_UTILS=ON \
   -DLLVM_BUILD_TOOLS=ON \
   -DLLVM_ENABLE_ASSERTIONS=ON \