have a single job definition with matrix strategy, the build and env do not persist between jobs

.github/workflows/full-regression.yml

@@ -17,6 +17,10 @@ jobs:
     runs-on: ubuntu-latest
     env:
       CCACHE_DIR: ${{ github.workspace }}/.ccache
+    strategy:
+      max-parallel: 2
+      matrix:
+        idx: [ 0, 1, 2, 3 ]
 
     steps:
     - name: Checkout repository
@@ -67,29 +71,15 @@ jobs:
         cmake --build build
         ccache -s
 
-    - name: Analyze top-level examples folder, split into 8 seperate lists of input scripts
+    - name: Full regression tests, splitting the top-level example input into 4 lists
       shell: bash
       run: |
         source linuxenv/bin/activate
         python3 tools/regression-tests/run_tests.py \
                --lmp-bin=build/lmp \
                --config-file=tools/regression-tests/config_serial.yaml \
-               --examples-top-level=examples --analyze --num-workers=8
+               --examples-top-level=examples --analyze --num-workers=4
 
-  run_tests:
-    name: Full Regression Test
-    # restrict to official LAMMPS repository
-    if: ${{ github.repository == 'lammps/lammps' }}
-    runs-on: ubuntu-latest
-    strategy:
-      max-parallel: 2
-      matrix:
-        idx: [ 0, 1 ]
-
-    steps:
-    - name: Run regression tests
-      run: |
-        source linuxenv/bin/activate
         python3 tools/regression-tests/run_tests.py \
                --lmp-bin=build/lmp \
                --config-file=tools/regression-tests/config_serial.yaml \
@@ -101,3 +91,5 @@ jobs:
     - name: Upload artifacts
       uses: actions/upload-artifact@v4
 
+    
+