[mono][infra] Increase fullAOT LLVM CI timeout

[matouskozak]

The Mono fullAOT-llvm x64 job timeout to 480 minutes. It currently takes almost 6 hours just to compile the tests

These jobs are only run as part of runtime-llvm pipeline so it should be fine to let them run for longer but we if to be run on PRs we should consider more proper solution.

[matouskozak]

/azp run runtime-llvm

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Pull Request Overview

This PR increases the timeout for Mono fullAOT LLVM CI jobs from 400 to 480 minutes (8 hours) to accommodate longer compilation times. The change addresses current timeout issues where test compilation alone takes nearly 6 hours.

Key Changes

• Timeout increase from 400 to 480 minutes for LLVM fullAOT jobs
• Applied to both RuntimeTests and RuntimeIntrinsicsTests configurations

[kotlarmilos]

Instead of increasing the timeout, consider reducing the number of tests. Currently, the following test trees are being run:

testBuildArgs: >-
                    -tree:CoreMangLib -tree:Exceptions -tree:GC -tree:Interop -tree:Loader -tree:Regressions -tree:baseservices
                    -tree:ilasm -tree:ilverify -tree:managed -tree:profiler -tree:readytorun -tree:reflection -tree:tracing
                    -tree:JIT/BBT -tree:JIT/CodeGenBringUpTests -tree:JIT/Directed -tree:JIT/Generics -tree:JIT/IL_Conformance
                    -tree:JIT/Math -tree:JIT/Methodical -tree:JIT/PGO -tree:JIT/Performance -tree:JIT/Regression -tree:JIT/RyuJIT
                    -tree:JIT/Stress -tree:JIT/common -tree:JIT/jit64 -tree:JIT/opt -tree:JIT/superpmi

We could potentially exclude the ilasm, ilverify, readytorun, and PGO (or more) groups to reduce test execution time as they shouldn't be relevant for Mono LLVM.