Add more flake8 checks

[kaxil]

This PR adds more flake8 checks for enforcing best practises

[codecov]

Codecov Report

Merging #106 (0eb0688) into main (eb3a274) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #106   +/-   ##
=======================================
  Coverage   90.15%   90.15%           
=======================================
  Files          35       35           
  Lines        1890     1890           
=======================================
  Hits         1704     1704           
  Misses        186      186           

Impacted Files	Coverage Δ
astronomer/providers/amazon/aws/hooks/s3.py	94.95% <ø> (ø)
astronomer/providers/amazon/aws/sensors/s3.py	98.76% <ø> (ø)
...viders/cncf/kubernetes/operators/kubernetes_pod.py	86.04% <ø> (ø)
...oviders/cncf/kubernetes/triggers/wait_container.py	93.54% <ø> (ø)
...stronomer/providers/databricks/hooks/databricks.py	95.16% <ø> (ø)
...nomer/providers/google/cloud/operators/bigquery.py	100.00% <ø> (ø)
astronomer/providers/google/cloud/sensors/gcs.py	95.83% <ø> (ø)
astronomer/providers/http/hooks/http.py	88.73% <ø> (ø)
astronomer/providers/http/sensors/http.py	81.81% <ø> (ø)
astronomer/providers/http/triggers/http.py	67.85% <ø> (ø)
... and 1 more

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