Hparams: Fix internal Builder failure for test. (#6545)

Googlers, see cl/557139147 for failure.

The CL's presubmit passes because the tests are not run but fixing the
Builder failures seems like good hygiene.

Author: bmd3k

tensorboard/webapp/hparams/_redux/BUILD

@@ -170,6 +170,7 @@ tf_ts_library(
         "//tensorboard/webapp/testing:utils",
         "//tensorboard/webapp/webapp_data_source:http_client_testing",
         "@npm//@ngrx/effects",
+        "@npm//@ngrx/store",
         "@npm//@types/jasmine",
         "@npm//rxjs",
     ],