Add missing wait_for_granularity functions

The bst sulution to allow test to pass on file systems that only recored
mtime with 1 second resoultion had not been applied to some new tests.
diff --git a/tests/frontend/push.py b/tests/frontend/push.py
index 93b7425..fab32e2 100644
--- a/tests/frontend/push.py
+++ b/tests/frontend/push.py
@@ -223,6 +223,12 @@
         result = cli.run(project=project, args=['build', 'element1.bst'])
         result.assert_success()
 
+        # Something to do with the artifact share means we need two calls to
+        # wait_for_cache_franularity
+        # TODO: understand why to calls are needed
+        wait_for_cache_granularity()
+        wait_for_cache_granularity()
+
         # Create and build an element of 5 MB
         create_element_size('element2.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element2.bst'])
@@ -239,6 +245,12 @@
         assert_shared(cli, share, project, 'element1.bst')
         assert_shared(cli, share, project, 'element2.bst')
 
+        # Something to do with the artifact share means we need two calls to
+        # wait_for_cache_franularity
+        # TODO: understand why to calls are needed
+        wait_for_cache_granularity()
+        wait_for_cache_granularity()
+
         # Create and build another element of 5 MB (This will exceed the free disk space available)
         create_element_size('element3.bst', project, element_path, [], int(5e6))
         result = cli.run(project=project, args=['build', 'element3.bst'])
diff --git a/tests/frontend/track.py b/tests/frontend/track.py
index 808bf05..3450b07 100644
--- a/tests/frontend/track.py
+++ b/tests/frontend/track.py
@@ -9,7 +9,7 @@
 from buildstream.testing import cli  # pylint: disable=unused-import
 from buildstream._exceptions import ErrorDomain, LoadErrorReason
 from buildstream import _yaml
-from tests.testutils import generate_junction, yaml_file_get_provenance
+from tests.testutils import generate_junction, yaml_file_get_provenance, wait_for_cache_granularity
 from . import configure_project
 
 # Project directory
@@ -380,6 +380,8 @@
     states = cli.get_element_states(project, [target])
     assert states[target] == 'no reference'
 
+    wait_for_cache_granularity()
+
     # Perform the track
     result = cli.run(project=project, args=['source', 'track', target])
     result.assert_success()
@@ -388,6 +390,8 @@
 
     assert creation_mtime != track1_mtime
 
+    wait_for_cache_granularity()
+
     # Now (needlessly) track again
     result = cli.run(project=project, args=['source', 'track', target])
     result.assert_success()