Create History for Filebackend and DB Backend

[donaldcampbelljr]

Addresses: https://github.com/pepkit/pipestat/issues/177

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 12.64368% with 76 lines in your changes are missing coverage. Please review.

Project coverage is 54.01%. Comparing base (30bcccd) to head (8001551).

:exclamation: Current head 8001551 differs from pull request most recent head 2cf054c. Consider uploading reports for the commit 2cf054c to get more accurate results

Files	Patch %	Lines
pipestat/backends/db_backend/dbbackend.py	4.34%	44 Missing :warning:
pipestat/backends/db_backend/db_parsed_schema.py	4.54%	21 Missing :warning:
pipestat/pipestat.py	9.09%	10 Missing :warning:
pipestat/backends/file_backend/filebackend.py	87.50%	1 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## dev #178 +/- ## ========================================== - Coverage 55.56% 54.01% -1.56% ========================================== Files 15 15 Lines 2318 2405 +87 ========================================== + Hits 1288 1299 +11 - Misses 1030 1106 +76 ```

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[donaldcampbelljr]

Some suggested changes after today's discussion:

• move the created and modified time to a meta key and then have a history key under the meta key as well.
• instead of the current data structure, should change it to be a list of objects under each result identifier (timestamp - value) or (timestamp - action - value).
• filter out all meta data before returning to user unless they are specifically using the retrieve_history function
• don't duplicate any results. Currently the current result is also reported under history, we should strive to not do that.

[donaldcampbelljr]

Ok, I've added most of the above suggestions. File backend history now looks like this:

default_pipeline_name:
  project: {}
  sample:
    sample1:
      meta:
        pipestat_modified_time: '2024-04-16 15:34:57'
        pipestat_created_time: '2024-04-16 15:34:56'
        history:
          name_of_something:
            '2024-04-16 15:34:57': test_name
          number_of_things:
            '2024-04-16 15:34:57': 1
      name_of_something: MODIFIED_test_name
      number_of_things: 2