Merge pull request #7457 from artemry-mlnx/artemry-mlnx/reduce_mellanox_ci_time_v4

Mellanox Open MPI CI: optimized git checkout step to reduce CI duration (v4.0.x)

Author: hppritcha

.ci/mellanox/azure-pipelines.yml

@@ -29,10 +29,11 @@ jobs:
     inputs:
       sourceFolder: $(Pipeline.Workspace)
       contents: |
-        **/*
+        **/jenkins_scripts
   - checkout: self
     submodules: true
     path: ompi
+    clean: true
   - bash: |
       set -eE
       [ "$(debug)" = "true" ] && set -x