[Couchbase] Properly check the type of the query time values

[nmuesch]

What does this PR do?

Properly identify if the value returned is a subclass of the basestring type. Uses isinstance instead of type as type doesn't check for inheritance/sub classes, so we never actually hit the convert to seconds function.

Motivation

Customer reached out missing the Quey_time based metrics.

Testing Guidelines

An overview on testing
is available in our contribution guidelines.

Versioning

• Bumped the version check in manifest.json
• Updated CHANGELOG.md

Additional Notes

Anything else we should know when reviewing?

[bits-bot]

@nmuesch, thanks for your PR! By analyzing the history of the files in this pull request, we identified @gmmeyer to be a potential reviewer.