Import pytest types from pytest package, not private _pytest - requir…

[fizyk]

…e at least pytest 6.2 - closes #533

[codecov-commenter]

Codecov Report

Merging #535 (4e19c3e) into main (3faf1fa) will increase coverage by 0.60%.
The diff coverage is 28.57%.

@@            Coverage Diff             @@
##             main     #535      +/-   ##
==========================================
+ Coverage   74.23%   74.83%   +0.60%     
==========================================
  Files          22       22              
  Lines         617      616       -1     
==========================================
+ Hits          458      461       +3     
+ Misses        159      155       -4     

Flag	Coverage Δ
linux	74.35% <28.57%> (+0.12%)	⬆️
macos	68.01% <28.57%> (?)

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

Impacted Files	Coverage Δ
src/pytest_postgresql/config.py	77.77% <0.00%> (ø)
src/pytest_postgresql/factories/client.py	66.66% <0.00%> (ø)
src/pytest_postgresql/factories/noprocess.py	64.51% <0.00%> (ø)
src/pytest_postgresql/factories/process.py	61.90% <0.00%> (+1.43%)	⬆️
tests/test_executor.py	100.00% <100.00%> (ø)
tests/test_postgres_options_plugin.py	100.00% <100.00%> (ø)
src/pytest_postgresql/retry.py	64.70% <0.00%> (+17.64%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 1031c10...4e19c3e. Read the comment docs.