Revert "Add mapping to trigger NetworkSecurity unit tests on presubmit for tethering-mainline-presubmit"

This reverts commit f37bf52f86efa22784c14ea74b208a45e6b1741f.

Reason for revert: b/398885474

Change-Id: Ib5d6ee1fe2738518ba6c3de17c42bb59a673e6af
diff --git a/networksecurity/TEST_MAPPING b/networksecurity/TEST_MAPPING
index f75bf9a..448ee84 100644
--- a/networksecurity/TEST_MAPPING
+++ b/networksecurity/TEST_MAPPING
@@ -1,9 +1,4 @@
 {
-  "tethering-mainline-presubmit": [
-    {
-      "name": "NetworkSecurityUnitTests"
-    }
-  ],
   "presubmit": [
     {
       "name": "CtsNetSecConfigCertificateTransparencyTestCases"