Update `pytest` related dependencies, `coverage` especially

[scbedd]

It's been a while since we updated these. We need to bump all our downstream pytest dependencies.

• Update pinned requirements files under eng/
• Update any specific environments under eng/tox/tox.ini

Ensure coverage and pass reports are still uploaded after update of above.

[azure-sdk]

Label prediction was below confidence level 0.6 for Model:ServiceLabels: 'Storage:0.45099396,Azure.Core:0.20843807,Cosmos:0.020611463'
Label prediction was below confidence level 0.6 for Model:CategoryLabels: 'Client:0.5903203,Mgmt:0.39870757,Service:0.0056472686'

[scbedd]

Resolved as part of commits in #30159