[Test] Use `grpc_test_slowdown_factor` in `alts_concurrent_connectivity_test` (#37632)

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Closes #37632

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/37632 from yijiem:alts-concurrent-connectivity-test-flake 68df4b1327
PiperOrigin-RevId: 671117730

test/core/tsi/alts/handshaker/alts_concurrent_connectivity_test.cc

@@ -279,8 +279,8 @@ TEST(AltsConcurrentConnectivityTest, TestBasicClientServerHandshakes) {
   {
     ConnectLoopRunner runner(
         test_server.address(), fake_handshake_server.address(),
-        10 /* per connect deadline seconds */, 10 /* loops */,
-        GRPC_CHANNEL_READY /* expected connectivity states */,
+        10 * grpc_test_slowdown_factor() /* per connect deadline seconds */,
+        10 /* loops */, GRPC_CHANNEL_READY /* expected connectivity states */,
         0 /* reconnect_backoff_ms unset */);
   }
 }
@@ -298,8 +298,8 @@ TEST(AltsConcurrentConnectivityTest, TestConcurrentClientServerHandshakes) {
     for (size_t i = 0; i < num_concurrent_connects; i++) {
       connect_loop_runners.push_back(std::make_unique<ConnectLoopRunner>(
           test_server.address(), fake_handshake_server.address(),
-          15 /* per connect deadline seconds */, 5 /* loops */,
-          GRPC_CHANNEL_READY /* expected connectivity states */,
+          15 * grpc_test_slowdown_factor() /* per connect deadline seconds */,
+          5 /* loops */, GRPC_CHANNEL_READY /* expected connectivity states */,
           0 /* reconnect_backoff_ms unset */));
     }
     connect_loop_runners.clear();
@@ -336,7 +336,8 @@ TEST(AltsConcurrentConnectivityTest,
     for (size_t i = 0; i < num_concurrent_connects; i++) {
       connect_loop_runners.push_back(std::make_unique<ConnectLoopRunner>(
           fake_backend_server.address(), fake_handshake_server.address(),
-          10 /* per connect deadline seconds */, 3 /* loops */,
+          10 * grpc_test_slowdown_factor() /* per connect deadline seconds */,
+          3 /* loops */,
           GRPC_CHANNEL_TRANSIENT_FAILURE /* expected connectivity states */,
           0 /* reconnect_backoff_ms unset */));
     }
@@ -368,7 +369,8 @@ TEST(AltsConcurrentConnectivityTest,
     for (size_t i = 0; i < num_concurrent_connects; i++) {
       connect_loop_runners.push_back(std::make_unique<ConnectLoopRunner>(
           fake_backend_server.address(), fake_handshake_server.address(),
-          20 /* per connect deadline seconds */, 2 /* loops */,
+          20 * grpc_test_slowdown_factor() /* per connect deadline seconds */,
+          2 /* loops */,
           GRPC_CHANNEL_TRANSIENT_FAILURE /* expected connectivity states */,
           0 /* reconnect_backoff_ms unset */));
     }
@@ -400,7 +402,8 @@ TEST(AltsConcurrentConnectivityTest,
     for (size_t i = 0; i < num_concurrent_connects; i++) {
       connect_loop_runners.push_back(std::make_unique<ConnectLoopRunner>(
           fake_backend_server.address(), fake_handshake_server.address(),
-          10 /* per connect deadline seconds */, 2 /* loops */,
+          10 * grpc_test_slowdown_factor() /* per connect deadline seconds */,
+          2 /* loops */,
           GRPC_CHANNEL_TRANSIENT_FAILURE /* expected connectivity states */,
           100 /* reconnect_backoff_ms */));
     }