install python for blst nightly checks before building instead of aft…

…er (#471)

* install python for blst nightly checks before building instead of after

* Update build-blst-nightly.yml

.github/workflows/build-blst-nightly.yml

@@ -23,6 +23,11 @@ jobs:
     - name: Checkout code
       uses: actions/checkout@v4
 
+    - name: Install Python
+      uses: chia-network/actions/setup-python@main
+      with:
+        python-version: '3.10'
+
     - name: Ubuntu build C++ and test blst at origin/main
       if: startsWith(matrix.os, 'ubuntu')
       # blst is still using master instead of main
@@ -59,11 +64,6 @@ jobs:
         echo "Running runtest"
         build\src\Debug\runtest.exe
   
-    - name: Install Python
-      uses: actions/setup-python@v4
-      with:
-        python-version: '3.9'
-
     - name: Test pure python implementation
       run: |
         python python-impl/impl-test.py