Set RuntimeType explicitly for wasm and wasm_coreclr micro benchmarks

[ilonatommy]

Problem

Coreclr jobs are running fine, see: dotnet/runtime#125566 runtime-wasm-perf (Build Performance micro wasm_coreclr wasm coreclr_v8 linux x64 perfviper net11.0) but we don't get autofilling issues on them, like we do for mono.

Root cause

wasm_coreclr benchmark results are never reported to the perf autofiling system. The allTestHistory dashboard has zero wasm_coreclr entries despite the job running in CI.

--runtime-flavor is only passed via YAML for MAUI scenarios, so for wasm micro benchmarks runtime_flavor is None. This means:

• wasm_coreclr: RuntimeType=None in configurations -> data lands in the wrong blob storage path and is never picked up by the autofiler,
• wasm: RuntimeType not set at all in configurations ->happens to work but is implicit.

Fix

Auto-detect runtime_flavor from runtime_type for wasm micro benchmarks in run_performance_job.py, matching the existing pattern used by Android and iOS scenarios.

Set RuntimeType in get_run_configurations() for both wasm and wasm_coreclr so the configuration metadata is explicit.

Impact

• wasm_coreclr: Fixes broken reporting — results will now appear in allTestHistory and be picked up by the perf autofiler
• wasm (Mono): Adds explicit RuntimeType=mono to configurations. This changes the blob storage path for new data (previously had no RuntimeType key), but makes the metadata correct and future-proof
• No impact on non-wasm scenarios

[pavelsavara]

I will leave the approval to @LoopedBard3

[pavelsavara]

would this break how the new data are compared to baseline or history ?