bmc/test: cleanup remove unused declarations

Remove unused using declarations.

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: If975e789745f4c625c84fba376d85f805f38f3e0
diff --git a/bmc/test/firmware_commit_unittest.cpp b/bmc/test/firmware_commit_unittest.cpp
index 6e24107..cb50b8e 100644
--- a/bmc/test/firmware_commit_unittest.cpp
+++ b/bmc/test/firmware_commit_unittest.cpp
@@ -14,12 +14,9 @@
 {
 namespace
 {
-using ::testing::_;
-using ::testing::IsNull;
-using ::testing::NotNull;
+
 using ::testing::Return;
 using ::testing::StrEq;
-using ::testing::StrictMock;
 
 class FirmwareHandlerCommitTest : public ::testing::Test
 {