[chore] revert temp fix for resource attributes (#702)

Co-authored-by: Joao Grassi <joao.grassi@dynatrace.com>
Co-authored-by: Josh Suereth <joshuasuereth@google.com>

model/registry/cloud.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.cloud
     prefix: cloud
-    type: resource
+    type: attribute_group
     brief: >
       A cloud environment (e.g. GCP, Azure, AWS).
     attributes:

model/registry/container.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.container
     prefix: container
-    type: resource
+    type: attribute_group
     brief: >
       A container instance.
     attributes:

model/registry/device.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.device
     prefix: device
-    type: resource
+    type: attribute_group
     brief: >
         Describes device attributes.
     attributes:

model/registry/host.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.host
     prefix: host
-    type: resource
+    type: attribute_group
     brief: >
       A host is defined as a computing instance. For example, physical servers, virtual machines, switches or disk array.
     attributes:

model/registry/oci.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.oci.manifest
     prefix: oci.manifest
-    type: resource
+    type: attribute_group
     brief: >
       An OCI image manifest.
     attributes:

model/registry/os.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.os
     prefix: os
-    type: resource
+    type: attribute_group
     brief: >
         The operating system (OS) on which the process represented by this resource is running.
     note: >

model/registry/process.yaml

@@ -1,7 +1,7 @@
 groups:
   - id: registry.process
     prefix: process
-    type: resource
+    type: attribute_group
     brief: >
         An operating system process.
     attributes: