Extend stress timeouts for merged tests (#68523)

As we're intentionally running larger merged tests in-proc to reduce
runtime overhead, we've become prone to hitting various infra
timeouts. As part of the switchover I extended the default test
timeout from 15 to 30 minutes; I hovewer overlooked the fact that
the run.py script manually overrides this value for GC stress and
other special test build / execution flavors. This change doubles
all these timeouts to cater for the larger merged test apps.

Thanks

Tomas

src/tests/run.py

@@ -849,14 +849,14 @@ def run_tests(args,
 
     # Setup the environment
     if args.long_gc:
-        print("Running Long GC Tests, extending timeout to 20 minutes.")
-        per_test_timeout = 20*60*1000
+        print("Running Long GC Tests, extending timeout to 40 minutes.")
+        per_test_timeout = 40*60*1000
         print("Setting RunningLongGCTests=1")
         os.environ["RunningLongGCTests"] = "1"
 
     if args.gcsimulator:
-        print("Running GCSimulator tests, extending timeout to one hour.")
-        per_test_timeout = 60*60*1000
+        print("Running GCSimulator tests, extending timeout to two hours.")
+        per_test_timeout = 120*60*1000
         print("Setting RunningGCSimulatorTests=1")
         os.environ["RunningGCSimulatorTests"] = "1"
 
@@ -874,18 +874,14 @@ def run_tests(args,
         print("Large Version Bubble enabled")
         os.environ["LargeVersionBubble"] = "true"
 
-    if gc_stress:
-        print("Running GCStress, extending timeout to 120 minutes.")
-        per_test_timeout = 120*60*1000
-
     if args.limited_core_dumps:
         setup_coredump_generation(args.host_os)
 
     if args.run_in_context:
         print("Running test in an unloadable AssemblyLoadContext")
         os.environ["CLRCustomTestLauncher"] = args.runincontext_script_path
         os.environ["RunInUnloadableContext"] = "1";
-        per_test_timeout = 20*60*1000
+        per_test_timeout = 40*60*1000
 
     if args.tiering_test:
         print("Running test repeatedly to promote methods to tier1")
@@ -895,6 +891,10 @@ def run_tests(args,
         print("Running tests NativeAOT")
         os.environ["CLRCustomTestLauncher"] = args.nativeaottest_script_path
 
+    if gc_stress:
+        per_test_timeout *= 8
+        print("Running GCStress, extending test timeout to cater for slower runtime.")
+
     # Set __TestTimeout environment variable, which is the per-test timeout in milliseconds.
     # This is read by the test wrapper invoker, in src\tests\Common\Coreclr.TestWrapper\CoreclrTestWrapperLib.cs.
     print("Setting __TestTimeout=%s" % str(per_test_timeout))