feat: add driver connection lifecycle mgmt to adhere to neo4j Driver expectations

[jtanningbed]

Description

From neo4j driver impl:

 def __del__(
    self,
    _unclosed_resource_warn=unclosed_resource_warn,
    _is_async_code=Util.is_async_code,
    _deprecation_warn=deprecation_warn,
):
    if not self._closed:
        _unclosed_resource_warn(self)
    # TODO: 6.0 - remove this
    if _is_async_code:
        return
    if not self._closed:
        _deprecation_warn(
            "Relying on Driver's destructor to close the session "
            "is deprecated. Please make sure to close the session. "
            "Use it as a context (`with` statement) or make sure to "
            "call `.close()` explicitly. Future versions of the "
            "driver will not close drivers automatically."
        )
        self.close()

We're currently relying on the driver destructor/python garbage collection. This PR adds basic context management which:

• enables use of graph connection using with statement.
• enables explicit close() of driver connection
• raises RuntimeError when using closed connection

Type of Change

• New feature

Complexity

Low

How Has This Been Tested?

• Unit tests
• Integration tests
• Manual tests

Checklist

• Unit tests updated
• Integration tests updated
• CHANGELOG.md updated

[alexthomas93]

LGTM. Just a small update to the tests needed. Thanks for your contribution!