utils/metrics: Move to lib

utils/metrics depends on chromite.lib, and is written such that it
contains logic a little too coupled to CrOS/chromite implementation
detials to qualify for utils.

BUG=b:223433932
TEST=run_tests, CQ

Change-Id: Ia9a21e4f97b42e13f2443c8007412ef31b9d80af
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3595160
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Alex Klein <saklein@chromium.org>
Tested-by: Alex Klein <saklein@chromium.org>
diff --git a/api/controller/image.py b/api/controller/image.py
index 820abb2..1661f68 100644
--- a/api/controller/image.py
+++ b/api/controller/image.py
@@ -25,11 +25,11 @@
 from chromite.lib import constants
 from chromite.lib import cros_build_lib
 from chromite.lib import image_lib
+from chromite.lib import metrics_lib
 from chromite.lib import sysroot_lib
 from chromite.service import packages as packages_service
 from chromite.scripts import pushimage
 from chromite.service import image
-from chromite.utils import metrics
 
 if TYPE_CHECKING:
   from chromite.api import api_config
@@ -210,7 +210,7 @@
 @faux.empty_completed_unsuccessfully_error
 @validate.require('build_target.name')
 @validate.validation_complete
-@metrics.collect_metrics
+@metrics_lib.collect_metrics
 def Create(input_proto: 'image_pb2.CreateImageRequest',
            output_proto: 'image_pb2.CreateImageResult',
            _config: 'api_config.ApiConfig'):