modified model_config.yaml, replaced '???' with '/placeholder/path' to overcome problamatic early validations in nemo framework.

While the correct approach will be to fix the problem in the nemo repository, this is much faster, and seems other nvidia models have some values there in the json anyhow and therefore avoid this issue.
notice this value is expected to be overriden by custom config/arguments yet some validations happen too early and raise an exception on missing values

stt_pt_fastconformer_hybrid_large_pc.nemo

@@ -1,3 +1,3 @@
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+oid sha256:d9ca9fa64e39ed70743ba760a67df89f6dfcaf85dea0fd145c479cdcbbb03f38
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