Tests | Fix random test failures

[cheenamalhotra]

NotADatabase exception mismatch errors:

• Compare error contents not object references

Transaction Deadlocked errors:

• Rerun transaction as per recommended action.

KeyStoreProvider error mismatch:

• Cleanup registered providers and run test cleanly.
• Check for Contains instead of Equals for error messages.

Host name not found in "CreateCertificate()"

• Reduced calls to CreateCertificate in same test class by making certificate static as it's not expected to change.

ConnectionSpeed Test improvements

• Compare divided value as double
• Disabled temporarily as it fails more often and not reproducible locally.