Bump Npgsql from 5.0.10 to 6.0.1

Bumps [Npgsql](https://github.com/npgsql/npgsql) from 5.0.10 to 6.0.1.
- [Release notes](https://github.com/npgsql/npgsql/releases)
- [Commits](npgsql/npgsql@v5.0.10...v6.0.1)

---
updated-dependencies:
- dependency-name: Npgsql
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

src/common.props

@@ -15,7 +15,7 @@
     <XunitVersion>2.4.1</XunitVersion>
     <XunitRunnerVersion>2.4.3</XunitRunnerVersion>
     <AkkaVersion>1.4.28</AkkaVersion>
-    <PostgresVersion>5.0.10</PostgresVersion>
+    <PostgresVersion>6.0.1</PostgresVersion>
     <NetStandardLibVersion>netstandard2.0</NetStandardLibVersion>
     <NetFrameworkVersion>net45</NetFrameworkVersion>
     <TestSdkVersion>17.0.0</TestSdkVersion>