[moblab] fix wmatrix not updating due to bad imports

wmatrix update scripts try to import whining, but that
package does not exist, and is not used anywhere in
any of the update scripts that imported it. Removing
it and wmatrix updater runs without errors, tests
show up shortly after completion as expected.

BUG=chromium:833521
TEST=Build and test on local device that recently run
tests appear on wmatrix.

Change-Id: I77d1e8f1b96d693af2d54757b2c7f587274d7396
Reviewed-on: https://chromium-review.googlesource.com/1015765
Commit-Ready: Matt Mallett <mattmallett@chromium.org>
Tested-by: Matt Mallett <mattmallett@chromium.org>
Reviewed-by: Jacob Kopczynski <jkop@chromium.org>
diff --git a/src/backend/update_lib.py b/src/backend/update_lib.py
index cff9eb1..c404812 100644
--- a/src/backend/update_lib.py
+++ b/src/backend/update_lib.py
@@ -13,8 +13,6 @@
 import logging
 import time
 
-import whining
-
 from chromite.lib import metrics
 from infra_libs import ts_mon
 from src import settings
diff --git a/src/backend/update_rawdb.py b/src/backend/update_rawdb.py
index 5f15da1..6dc5a1e 100644
--- a/src/backend/update_rawdb.py
+++ b/src/backend/update_rawdb.py
@@ -11,8 +11,6 @@
 import time
 import logging
 
-import whining
-
 from chromite.lib import metrics
 from chromite.lib import ts_mon_config
 from src import settings
diff --git a/src/backend/update_wmdb.py b/src/backend/update_wmdb.py
index d88d2a5..87d52f4 100644
--- a/src/backend/update_wmdb.py
+++ b/src/backend/update_wmdb.py
@@ -10,8 +10,6 @@
 import time
 import logging
 
-import whining
-
 from chromite.lib import metrics
 from chromite.lib import ts_mon_config
 from infra_libs import ts_mon