Increase timeout for ARM64 testing (#70551)

We're seeing Windows ARM64 workitems being stuck in the Helix queue for more than 90 minutes.

Author: MichalStrehovsky

eng/pipelines/runtime.yml

@@ -261,7 +261,7 @@ jobs:
       isSingleFile: true
       nameSuffix: NativeAOT
       buildArgs: -s clr.alljits+clr.tools+clr.nativeaotlibs+clr.nativeaotruntime+libs+libs.tests -c $(_BuildConfig) /p:TestNativeAot=true /p:ArchiveTests=true
-      timeoutInMinutes: 120
+      timeoutInMinutes: 180
       # extra steps, run tests
       extraStepsTemplate: /eng/pipelines/libraries/helix.yml
       extraStepsParameters: