test: use one workflow to run all tests

With `none` parameter added to matrix only one workflow
is needed to run all tests (with and without Valgrind)

Signed-off-by: Tomasz Gromadzki <tomasz.gromadzki@intel.com>

.github/workflows/pmem_valgrind.yml

@@ -18,7 +18,7 @@ jobs:
       fail-fast: false
       matrix:
         script: ['sh', 'py']
-        config: ['drd', 'pmemcheck', 'memcheck', 'helgrind']
+        config: ['none', 'drd', 'pmemcheck', 'memcheck', 'helgrind']
         build: ['debug', 'nondebug']
         os: [[self-hosted, rhel],[self-hosted, opensuse]]