Fix raising exception on multiple schemas

[tnguyenhv]

Hello! I'm unsure of the intended behavior of this library when multiple schemas are provided for an endpoint, but I do know a KeyError occurs when one schema fails before another is processed (in my case when a failed to validate request schema precedes a successful query schema). I updated the way the errors are added onto the BadRequest by just merging the schema_errors from all the failing schemas inside of BadRequest.data['errors']['schema_errors'].

This is the error when using both request and query validation and request fails:

  File "/Users/chaz/hv/core.hivelocity.net/venv/lib/python3.8/site-packages/flask_accepts/decorators/decorators.py", line 158, in inner
    error.data["errors"].update({"schema_errors": schema_error})
KeyError: 'errors'

[codecov-commenter]

Codecov Report

Patch coverage: 100.00% and project coverage change: +0.02 🎉

Comparison is base (0556746) 98.44% compared to head (facfafe) 98.46%.

📣 This organization is not using Codecov’s GitHub App Integration. We recommend you install it so Codecov can continue to function properly for your repositories. Learn more

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #119      +/-   ##
==========================================
+ Coverage   98.44%   98.46%   +0.02%     
==========================================
  Files           7        7              
  Lines        1285     1303      +18     
==========================================
+ Hits         1265     1283      +18     
  Misses         20       20              

Impacted Files	Coverage Δ
flask_accepts/decorators/decorators.py	98.68% <100.00%> (+0.01%)	⬆️
flask_accepts/decorators/decorators_test.py	97.53% <100.00%> (+0.05%)	⬆️

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

☔ View full report in Codecov by Sentry.
📢 Do you have feedback about the report comment? Let us know in this issue.