Remove old reference to run_gtest_angle_test.py.

We should've removed this in https://crrev.com/c/2280255; by
leaving it in, the chromium build still tries to include it
when building fuchsia packages, even though it isn't needed.

TBR=jmadill@chromium.org
Bug: angleproject:3162
Change-Id: I6314a88e276b4459534344d500345ccf5de2b649
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2281553
Reviewed-by: Dirk Pranke <dpranke@google.com>
Commit-Queue: Dirk Pranke <dpranke@google.com>

gni/angle.gni

@@ -371,11 +371,6 @@ template("angle_test") {
     }
     data = invoker.data + [
              "$angle_root/scripts/run_gtest_angle_test.py",
-
-             # TODO(anglebug.com/3162): Remove the reference to the
-             # //testing/scripts copy of run_gtest_angle_test.py.
-             "//testing/scripts/run_gtest_angle_test.py",
-
              "//testing/scripts/common.py",
              "//testing/xvfb.py",
            ]