[FIX] odoo: bad imports in tests don't fail silently anymore

Before this fix, you can break a test class by simply adding an
incorrect import like this:
`from gloubiboulga import Casimir`
--> No error message, the test is simply not run

This is due to the fact that we want to ignore ImportError's... only
when there is no `.tests` submodules (actually, we ignored them all!)

This commit fixes the condition and re-enables error logging when tests
actually encounter ImportErrors

odoo/modules/module.py

@@ -432,12 +432,19 @@ def get_test_modules(module):
     modpath = 'odoo.addons.' + module
     try:
         mod = importlib.import_module('.tests', modpath)
+    except ImportError as e:  # will also catch subclass ModuleNotFoundError of P3.6
+        # Hide ImportErrors on `tests` sub-module, but display other exceptions
+        if pycompat.PY2:
+            if e.message.startswith('No module named') and e.message.endswith("tests"):
+                return []
+        else:
+            if e.name == modpath + '.tests' and e.msg.startswith('No module named'):
+                return []
+        _logger.exception('Can not `import %s`.', module)
+        return []
     except Exception as e:
-        # If module has no `tests` sub-module, no problem.
-        if not pycompat.text_type(e).startswith(u'No module named'):
-            _logger.exception('Can not `import %s`.', module)
+        _logger.exception('Can not `import %s`.', module)
         return []
-
     if hasattr(mod, 'fast_suite') or hasattr(mod, 'checks'):
         _logger.warn(
             "Found deprecated fast_suite or checks attribute in test module "