Building path using os library instead of f-strings for real time analysis

[ijpulidos]

Description

Resolves #615 by using the os.path.join method instead of relying on manually introduced f-strings.

Todos

• Implement feature / fix bug
• Add tests
• Update changelog to summarize changes in behavior, enhancements, and bugfixes implemented in this PR

Status

• Ready to go

Changelog

Bug in generating real time analysis output when reporter is in the same working directory. Fixed by using ``os.path.join`` for creating the output path.

[ijpulidos]

It might seem trivial, but does it make sense to create a test for this? It can be something that checks running some short simulation and outputs the real time analysis file in the current working directory.

[zhang-ivy]

Previously, I was having trouble when feeding a file with no directory to the reporter, e.g. analysis.yaml. I had to change this to be ./analysis.yaml, but I think we should make sure that specifying only a file works as well. Can we make sure this PR allows this?

[ijpulidos]

@zhang-ivy Yes, I guess you mean specifying output.nc or similar when instantiating the reporter. And yes, this is exactly the problem that this solves, when you don't specify a directory for the reporter its directory attribute becomes an empty string and that is fine with os.path.join. That is, os.path.join('', 'output.nc') returns 'output.nc' as expected.

[zhang-ivy]

Great!

[mikemhenry]

LGTM!
For the refactor, we should try and use pathlib for everything