scouting: Change background_task implementation

Instead of manually implementing a ticker, this patch switches over to
using `time.Ticker`. The functionality should be identical.

This patch also adds a small test to make sure that the bare
functionality is working.

Signed-off-by: Philipp Schrader <philipp.schrader@gmail.com>
Change-Id: I54acfc5280b3541f3021dbe35d79e7db0adcc5f6
diff --git a/scouting/background_task/BUILD b/scouting/background_task/BUILD
index 20726ca..bdf7190 100644
--- a/scouting/background_task/BUILD
+++ b/scouting/background_task/BUILD
@@ -1,4 +1,4 @@
-load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 
 go_library(
     name = "background_task",
@@ -7,3 +7,9 @@
     target_compatible_with = ["@platforms//cpu:x86_64"],
     visibility = ["//visibility:public"],
 )
+
+go_test(
+    name = "background_task_test",
+    srcs = ["background_task_test.go"],
+    embed = [":background_task"],
+)