internal/awscloud: fix cloud-init userdata for secure instance

The conditional only checked if the cloudwatch group was set, and if it
wasn't, the hostname variable wouldn't be set either. So the executor
would try to look for a hostname but not find any.

internal/cloud/awscloud/secure-instance.go

@@ -22,12 +22,18 @@ type SecureInstance struct {
 func SecureInstanceUserData(cloudWatchGroup, hostname string) string {
 	additionalFiles := ""
 
-	if cloudWatchGroup != "" {
-		additionalFiles += fmt.Sprintf(`  - path: /tmp/cloud_init_vars
+	if cloudWatchGroup != "" || hostname != "" {
+		additionalFiles += `  - path: /tmp/cloud_init_vars
     content: |
-      OSBUILD_EXECUTOR_CLOUDWATCH_GROUP='%s'
-      OSBUILD_EXECUTOR_HOSTNAME='%s'
-`, cloudWatchGroup, hostname)
+`
+	}
+	if cloudWatchGroup != "" {
+		additionalFiles += fmt.Sprintf(`      OSBUILD_EXECUTOR_CLOUDWATCH_GROUP='%s'
+`, cloudWatchGroup)
+	}
+	if hostname != "" {
+		additionalFiles += fmt.Sprintf(`      OSBUILD_EXECUTOR_HOSTNAME='%s'
+`, hostname)
 	}
 
 	return fmt.Sprintf(`#cloud-config

internal/cloud/awscloud/secure-instance_test.go

@@ -33,7 +33,28 @@ write_files:
       OSBUILD_EXECUTOR_HOSTNAME='test-hostname'
 `,
 		},
-	}
+		{
+			Hostname: "test-hostname",
+			ExpectedUserData: `#cloud-config
+write_files:
+  - path: /tmp/worker-run-executor-service
+    content: ''
+  - path: /tmp/cloud_init_vars
+    content: |
+      OSBUILD_EXECUTOR_HOSTNAME='test-hostname'
+`,
+		},
+		{
+			CloudWatchGroup: "test-group",
+			ExpectedUserData: `#cloud-config
+write_files:
+  - path: /tmp/worker-run-executor-service
+    content: ''
+  - path: /tmp/cloud_init_vars
+    content: |
+      OSBUILD_EXECUTOR_CLOUDWATCH_GROUP='test-group'
+`,
+		}}
 
 	for idx, tc := range testCases {
 		t.Run(fmt.Sprintf("Test case %d", idx), func(t *testing.T) {