Instrument newer versions of the postgres jdbc SDK

[timja]

Is your feature request related to a problem? Please describe.
Postgres is not instrumented correctly by the agent

Describe the solution you would like
Update the code to support newer postgres SDK versions

Describe alternatives you have considered
We're currently manually instrumenting using the agent XML in some places but we have a lot of java applications that are missing out on this functionality.

Additional context
Need to update these lines of code:
https://github.com/Microsoft/ApplicationInsights-Java/blob/master/agent/src/main/java/com/microsoft/applicationinsights/agent/internal/agent/sql/PreparedStatementClassDataProvider.java#L63
https://github.com/Microsoft/ApplicationInsights-Java/blob/master/agent/src/main/java/com/microsoft/applicationinsights/agent/internal/agent/sql/PreparedStatementClassDataProvider.java#L222

To handle this commit:
pgjdbc/pgjdbc@42c2e3b#diff-fc136162d0d2039cce76db7d26c9ba04

Specifically the rename from:
AbstractJdbc2Connection -> PgConnection

[dhaval24]

@timja thank you very much for raising a feature request. PostGres, is something we don't have official auto collection support for, and hence you see its untouched for long. We will take this as a feature request and triage it to future feature releases.

@nikmd23, here is a feature request for PostGres.

@timja by the way, feel free to submit a PR if you would be willing to contribute to the project. We welcome all contributions!