Call close() in TearDown()

Bug: 251580081
Test: atest VtsHalGnssTargetTest
Change-Id: Ieb02205f434899f7e9c5db32cfa7172788c39fa6
diff --git a/gnss/aidl/vts/gnss_hal_test.h b/gnss/aidl/vts/gnss_hal_test.h
index 645fc82..c49c1b9 100644
--- a/gnss/aidl/vts/gnss_hal_test.h
+++ b/gnss/aidl/vts/gnss_hal_test.h
@@ -64,6 +64,7 @@
 
     virtual void SetUp() override;
     virtual void SetUpGnssCallback() override;
+    virtual void TearDown() override;
 
     void CheckLocation(const android::hardware::gnss::GnssLocation& location,
                        const bool check_speed);