feat(#1127): raise startup app error from es connection error

[frascuchon]

By raising the error with from clause, you can separate errors details from the main error message. You will see an error like:

opensearchpy.exceptions.ConnectionTimeout: ConnectionTimeout caused by - ReadTimeoutError(HTTPConnectionPool(host='localhost', port=9200): Read timed out. (read timeout=10))

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/anaconda3/envs/rubrix/lib/python3.8/site-packages/starlette/routing.py", line 526, in lifespan
    async for item in self.lifespan_context(app):
  File "/usr/local/anaconda3/envs/rubrix/lib/python3.8/site-packages/starlette/routing.py", line 467, in default_lifespan
    await self.startup()
  File "/usr/local/anaconda3/envs/rubrix/lib/python3.8/site-packages/starlette/routing.py", line 502, in startup
    await handler()
  File "/usr/local/anaconda3/envs/rubrix/lib/python3.8/site-packages/rubrix/server/server.py", line 101, in configure_elasticsearch
    raise ConfigError(
pydantic.errors.ConfigError: Your Elasticsearch endpoint at http://localhost:9200 is not available or not responding.
Please make sure your Elasticsearch instance is launched and correctly running and
you have the necessary access permissions. Once you have verified this, restart the Rubrix server.

Closes #1127

[codecov]

Codecov Report

Merging #1145 (60df22c) into master (304a9ad) will increase coverage by 0.17%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1145      +/-   ##
==========================================
+ Coverage   95.05%   95.22%   +0.17%     
==========================================
  Files         121      122       +1     
  Lines        4567     4798     +231     
==========================================
+ Hits         4341     4569     +228     
- Misses        226      229       +3     

Flag	Coverage Δ
pytest	95.22% <ø> (+0.17%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/rubrix/server/server.py	80.85% <ø> (ø)
src/rubrix/client/sdk/datasets/models.py	100.00% <0.00%> (ø)
...rubrix/labeling/text_classification/weak_labels.py	100.00% <0.00%> (ø)
...ubrix/labeling/text_classification/label_errors.py	100.00% <0.00%> (ø)
src/rubrix/client/datasets.py	98.19% <0.00%> (ø)
src/rubrix/client/rubrix_client.py	92.77% <0.00%> (+0.24%)	⬆️
src/rubrix/__init__.py	85.41% <0.00%> (+0.31%)	⬆️
src/rubrix/client/models.py	100.00% <0.00%> (+1.08%)	⬆️

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[dcfidalgo]

perfect 👌