[Backport 2.x] Add permission for get workflow step (#3940)

Backport b8a315a from #3937.

Signed-off-by: owaiskazi19 <owaiskazi19@gmail.com>
Signed-off-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

config/roles.yml

@@ -395,3 +395,4 @@ flow_framework_read_access:
     - 'cluster:admin/opensearch/flow_framework/workflow/search'
     - 'cluster:admin/opensearch/flow_framework/workflow_state/get'
     - 'cluster:admin/opensearch/flow_framework/workflow_state/search'
+    - 'cluster:admin/opensearch/flow_framework/workflow_step/get'