Add update provider to SELinux policy

WARNING: Using this attribute will result in failing CTS!

- Adds the update_provider attribute definition
- Adds the attribute to the allowlist for neverallow rules in apexd and
  domain

Bug: 375420598
Test: m
Test: atest android.security.cts.SELinuxHostTest#testNoExemptionsForUpdateInterfaces
Change-Id: I3fb8fa2537cd4c857ce0bd5ae1e8a5f9a2dc8a32
diff --git a/private/attributes b/private/attributes
index c89d0c7..7e25e94 100644
--- a/private/attributes
+++ b/private/attributes
@@ -22,3 +22,8 @@
 attribute sdk_sandbox_current;
 # Common to adbd and adbd_tradeinmode.
 attribute adbd_common;
+
+# Provides access to platform update services.
+# WARNING: USING THE update_provider ATTRIBUTE WILL CAUSE CTS TO FAIL!
+attribute update_provider;
+expandattribute update_provider false;