[WIP]Llama2 streaming

[lxning]

Description

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Please include a summary of the feature or issue being fixed. Please also include relevant motivation and context. List any dependencies that are required for this change.

Fixes #(issue)

Type of change

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• Bug fix (non-breaking change which fixes an issue)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• New feature (non-breaking change which adds functionality)
• This change requires a documentation update

Feature/Issue validation/testing

Please describe the Unit or Integration tests that you ran to verify your changes and relevant result summary. Provide instructions so it can be reproduced.
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• Test A
  Logs for Test A

• Test B
  Logs for Test B

Checklist:

• Did you have fun?
• Have you added tests that prove your fix is effective or that this feature works?
• Has code been commented, particularly in hard-to-understand areas?
• Have you made corresponding changes to the documentation?

[codecov]

Codecov Report

Merging #2705 (0e57d9c) into master (7f4419f) will not change coverage.
The diff coverage is n/a.

❗ Current head 0e57d9c differs from pull request most recent head 0e88030. Consider uploading reports for the commit 0e88030 to get more accurate results

@@           Coverage Diff           @@
##           master    #2705   +/-   ##
=======================================
  Coverage   72.44%   72.44%           
=======================================
  Files          85       85           
  Lines        3963     3963           
  Branches       58       58           
=======================================
  Hits         2871     2871           
  Misses       1088     1088           
  Partials        4        4           

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[lxning]

Close this PR since TP llama with continuous batching can have better performance