ci:oneapi: remove unused env var, specify --parallel for clarity

Author: scivision

.github/workflows/intel-oneapi.yml

@@ -1,7 +1,6 @@
 name: intel-oneapi
 
 env:
-  CMAKE_GENERATOR: Ninja
   CC: icx
   FC: ifx
 
@@ -52,7 +51,7 @@ jobs:
       run: cmake -S scripts -B scripts/build -DCMAKE_INSTALL_PREFIX=${{ runner.temp }}
 
     - name: Build/install HDF5
-      run: cmake --build scripts/build || cmake --build scripts/build
+      run: cmake --build scripts/build --parallel || cmake --build scripts/build -v
 # double build to workaround HDF5 build bug--can't find MPI_C first time.
 
     - name: Configure h5fortran
@@ -63,12 +62,12 @@ jobs:
       run: cat build/CMakeFiles/CMakeError.log
 
     - name: Release build
-      run: cmake --build --preset release
+      run: cmake --build --preset release --parallel
     - name: Release unit test
       run: ctest --preset release --output-junit test-release-oneapi.xml
 
     - name: debug build
-      run: cmake --build --preset debug
+      run: cmake --build --preset debug --parallel
     - name: debug unit test
       run: ctest --preset debug --output-junit test-debug-oneapi.xml