Do not build module-build-macros when all the components will be reused from previous module build.

module_build_service/models.py

@@ -133,6 +133,26 @@ class ModuleBuild(MBSBase):
                 if component.batch == self.batch
             ]
 
+    def up_to_current_batch(self, state=None):
+        """
+        Returns all components of this module in the current batch and
+        in the previous batches.
+        """
+
+        if not self.batch:
+            raise ValueError("No batch is in progress: %r" % self.batch)
+
+        if state != None:
+            return [
+                component for component in self.component_builds
+                if component.batch <= self.batch and component.state == state
+            ]
+        else:
+            return [
+                component for component in self.component_builds
+                if component.batch <= self.batch
+            ]
+
     def mmd(self):
         mmd = _modulemd.ModuleMetadata()
         try: