Import local infrared workspace if it exists

Change-Id: I9114730569a0caef0c7e838088c08c7ca8547a83

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 
 envlist = linters,py37,docs
-minversion = 2.3.2
+minversion = 3.4.0
 
 
 # --- unit test environments -------------------------------------------------
@@ -191,10 +191,11 @@ setenv =
     {[testenv:venv]setenv}
     IR_COMMAND={env:IR_COMMAND:{toxinidir}/tools/ci/ir}
     IR_HOME={env:IR_HOME:{envdir}/home/infrared}
-
-commands =
-    -infrared plugin remove tobiko
+commands_pre =
+    -ir plugin remove tobiko
     ir plugin add {toxinidir}/roles
+    -ir workspace import {env:IR_WORKSPACE_FILE:{toxinidir}/workspace.tgz}
+commands =
     ir tobiko --tobiko-src-dir {toxinidir} {posargs}