Create __repr__ for OCSClient

[BrianJKoopman]

Description

See title.

Motivation and Context

When working with many clients it's helpful to have a string representation for the OCSClient object.

How Has This Been Tested?

Tested on a local ocs sestup. Also wrote a new test for this.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• Unless I am preparing a release, I have opened this PR onto the develop branch.