Support NpgSql 6.x

[russcam]

This commit adds support for Npgsql 6.x, along with tests.
Update ProfiledApplication to allow passing MsBuild properties
to be able to test multiple dependent assembly versions.

Closes #1602

[ghost]

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• Reason: null

• Start Time: 2022-01-26T17:43:14.895+0000

• Duration: 87 min 48 sec

• Commit: 17e42ec

Test stats 🧪

Test	Results
Failed	0
Passed	24115
Skipped	136
Total	24251

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[gregkalapos]

Thanks! Planning to merge once #1605 is all green.