Use GTEST_SKIP for session tests

Bug: 251240681
Merged from https://widevine-internal-review.googlesource.com/180010

Change-Id: I39e5c0365a5e0c2ddf62e6f68426f6baa3ddd1a1

libwvdrmengine/oemcrypto/test/oemcrypto_license_test.h

@@ -39,6 +39,10 @@ class OEMCryptoSessionTests : public OEMCryptoClientTest {
 
   void SetUp() override {
     OEMCryptoClientTest::SetUp();
+    if (wvoec::global_features.derive_key_method ==
+        wvoec::DeviceFeatures::NO_METHOD) {
+      GTEST_SKIP() << "Test for devices that can derive session keys only.";
+    }
     EnsureTestROT();
     if (global_features.usage_table) {
       CreateUsageTableHeader();