aconfig: rename namespace -> package

What used to be referred to as a namespace is now called a package.

This CL is a semantic change only.

Bug: 285000854
Test: m nothing
Test: atest aconfig.test
Change-Id: If3fca67c415af75b44f316e16666b97089407069
diff --git a/tools/aconfig/protos/aconfig.proto b/tools/aconfig/protos/aconfig.proto
index 9d36a9e..489939c 100644
--- a/tools/aconfig/protos/aconfig.proto
+++ b/tools/aconfig/protos/aconfig.proto
@@ -40,12 +40,12 @@
 };
 
 message flag_declarations {
-  required string namespace = 1;
+  required string package = 1;
   repeated flag_declaration flag = 2;
 };
 
 message flag_value {
-  required string namespace = 1;
+  required string package = 1;
   required string name = 2;
   required flag_state state = 3;
   required flag_permission permission = 4;
@@ -65,7 +65,7 @@
 }
 
 message parsed_flag {
-  required string namespace = 1;
+  required string package = 1;
   required string name = 2;
   required string description = 3;
   required flag_state state = 4;