Fix check for serial port disabled (#3695)

* Fix check for serial port disabled

* fix check for block-project-ssh-keys

third_party/inspec/custom_functions/google_compute_instance.erb

@@ -109,19 +109,19 @@ end
 def block_project_ssh_keys
   return false if !defined?(@metadata['items']) || @metadata['items'].nil?
   @metadata['items'].each do |element|
-    return true if element.key=='block-project-ssh-keys' and element.value.casecmp('true').zero?
-    return true if element.key=='block-project-ssh-keys' and element.value=='1'
+    return true if element['key']=='block-project-ssh-keys' and element['value'].casecmp('true').zero?
+    return true if element['key']=='block-project-ssh-keys' and element['value']=='1'
   end
   false
 end
 
 def has_serial_port_disabled?
   return false if !defined?(@metadata['items']) || @metadata['items'].nil?
   @metadata['items'].each do |element|
-    return true if element.key=='serial-port-enable' and element.value.casecmp('false').zero?
-    return true if element.key=='serial-port-enable' and element.value=='0'
+    return false if element['key']=='serial-port-enable' and element['value'].casecmp('true').zero?
+    return false if element['key']=='serial-port-enable' and element['value']=='1'
   end
-  false
+  true
 end
 
 def has_disks_encrypted_with_csek?