Changed string handling to account for multiple responses

[bbixler500]

Attempts to fix ValueError when multiple values are returned because of timeout as is discussed in #651

Description

Changes internal logic so that only the most recent response string is used

Motivation and Context

Attempt to fix #651

How Has This Been Tested?

This has not been tested as of yet and I will update with a comment when it has.

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.

[ykyohei]

@bbixler500 The test is failed. Maybe we need to fix the test?

[bbixler500]

I'm not sure what these test errors are for. They seem to be in relation to the Lakeshore240 and Lakeshore425 so I don't know why they are showing up here

[ykyohei]

I tested this in a real system and didn't find any problems.
This edge case doesn't happen often, so I couldn't confirm the improvement for these edge cases during my testing, but I'm okay to merge this.

[BrianJKoopman]

I'm not sure what these test errors are for. They seem to be in relation to the Lakeshore240 and Lakeshore425 so I don't know why they are showing up here

Sorry, this was caused by a new release of OCS. Fixed in #664. Please merge in the latest from main.

[jlashner]

I'm approving this since it's been tested...

but reading through this I'm reminding myself how difficult this is to interpret, because PID message formats, and the results of these functions aren't documented. It would be great if someone who understands this could add some docs.