Fix ASR Buffered inference scripts

[titu1994]

What does this PR do ?

Add a one line overview of what this PR aims to accomplish.

Collection: [ASR]

Changelog

• Deepcopy the alignments before compute of alignments
• Do proper class level check of log level instead of incorrect config checks (older model doesn't have in config because the log=True is set by default inside of the function)

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PR Type:

• New Feature
• Bugfix
• Documentation

[fayejf]

LGTM. one thing we can discuss and add later: Could we add more tests regarding buffered inference? Is it necessary?

[titu1994]

Definitely need tests for buffered. I didn't add them before cause it was difficult to make it work but with the upgrades now it's easy to take a small pretrained model and add tests to overall + maybe unittests for the internals too.