use local channel in mamba instal

Author: alchem0x2A

.github/workflows/build-test.yml

@@ -69,8 +69,7 @@ jobs:
         CPU_COUNT=2 conda build .conda/
     - name: Install local build
       run: |
-        mamba install --help
-        mamba install --use-local sparc
+        mamba install -c local sparc
         which sparc
         ldd $(which sparc)
         ldd $(which mpirun)