Updates MSVSphere 9 excluded packages list

Excluded the following RHEL-specific packages:

  - ignition
  - insights-client
  - rust-coreos-installer

msvsphere-9.json

@@ -1,5 +1,11 @@
 {
     "excluded": {
+        "ignition": {
+            "reason": "RHEL-specific package."
+        },
+        "insights-client": {
+            "reason": "RHEL-specific package."
+        },
         "libica": {
             "reason": "s390x architecture-specific package."
         },
@@ -54,6 +60,9 @@
         "rhc-worker-playbook": {
             "reason": "RHEL-specific package."
         },
+        "rust-coreos-installer": {
+            "reason": "RHEL-specific package."
+        },
         "s390utils": {
             "reason": "s390x architecture-specific package."
         },