Update post-extraction processing workflow

[exfalsoquodlibet]

Added metadata info about extracted entities start and end character index and line number location to named_entities_all bigquery output table in src/post_extraction_process/post-extraction-gc-workflow.yaml

Checklists

This pull/merge request meets the following requirements:

• [x] code runs
• [x] developments are ethical and secure
• [x] you have made proportionate checks that the code works correctly
• [x] test suite passes
• [x] developments adhere to AQA plan (see docs/aqa/aqa_plan.md)
• [ ] data log updated (see docs/aqa/data_log.md), if necessary
• [ ] assumptions, and caveats log updated (see docs/aqa/assumptions_caveats.md), if necessary
• [x] minimum usable documentation written in the docs folder

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