Larmor: Lakeshore 625 Support

# Feature Description
As an instrument scientist I would like to be able to control my Lakeshore 625s remotely.

## Explanation
This will be a step towards our own SMSANS-SANS setup. The standard setup likely includes 3 Lakeshore 625s. An IOC and OPI is required.

### Additional Information
There is already Lakeshore 625 support in the community. This was written at DL to support the MICE experiment on ISIS. They have shared their code and this can be found on our team share (shares\ISIS_Experiment_Controls\Lakeshore625FromDL).

RD can arrange lone of a Lakeshore 625 (will need a trolley to move...) - to test the connectors should be shorted. A safety briefing should be sought at the point of borrowing it.

_{See our [Git Workflow](https://isiscomputinggroup.github.io/ibex_developers_manual/processes/git_and_github/Git-workflow.html).}

# Acceptance Criteria

- [ ] An IOC exists for the Lakeshore 625 with appropriate tests
* This should simply expose PVs corresponding to commands on the Lakeshore 625
* **Any cryogenic control logic (state machines etc) is out of scope**
- [ ] An OPI exists for the Lakeshore 625

# How to Review
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