Update language to comply with Android's inclusive language guidance

See https://source.android.com/setup/contribute/respectful-code for reference

#inclusivefixit

Bug: 161896447
Change-Id: Icb9e2fca7e27a2ee81380897134deae6c4a24053
Test: NA (Comment only)
diff --git a/payload_consumer/postinstall_runner_action_unittest.cc b/payload_consumer/postinstall_runner_action_unittest.cc
index 0041d31..cf5158b 100644
--- a/payload_consumer/postinstall_runner_action_unittest.cc
+++ b/payload_consumer/postinstall_runner_action_unittest.cc
@@ -227,7 +227,7 @@
   EXPECT_TRUE(processor_delegate_.processing_stopped_called_ ||
               processor_delegate_.processing_done_called_);
   if (processor_delegate_.processing_done_called_) {
-    // Sanity check that the code was set when the processor finishes.
+    // Validation check that the code was set when the processor finishes.
     EXPECT_TRUE(processor_delegate_.code_set_);
   }
 }