Add fix for GEOS-Chem Classic restart file path

[msulprizio]

GEOS-Chem Classic and GCHP restart files are now saved to a Restarts subdirectory.

This partially addresses issue #158, but as pointed out there it would be best to eventually specify the path in the configuration file.

[yantosca]

This is a simple fix that changes "restarts" to "Restarts". A further fix to specify the path in the configuration file can be made later, but this fix is sufficient to allow benchmark plotting to proceed without errors.

[laestrada]

Wouldn't this break backwards compatibility with GC?

[msulprizio]

Wouldn't this break backwards compatibility with GC?

Yes. Is it worth adding a is_gcc_pre_14.0 variable like we do for GCHP? Seems overkill but I'm happy to do it if that's what makes sense until we add a path to the config file.

[laestrada]

Wouldn't this break backwards compatibility with GC?

Yes. Is it worth adding a is_gcc_pre_14.0 variable like we do for GCHP? Seems overkill but I'm happy to do it if that's what makes sense until we add a path to the config file.

@msulprizio I think that it would otherwise cause the next few automated benchmark comparisons to fail because it would be looking for a Restarts/ directory in the ref version (eg. 14.0.1 vs 14.0.0), etc. I am happy to just implement the config file path sometime next week if that seems easier though.

[msulprizio]

A switch has now been added for is_gcc_pre_14_0