add vmfc tests. fix the psi4 vmfc g/h bug

[loriab]

• add in single-level and multi-level vmfc testing with excel references and job counts
• get to the bottom of psi4 vmfc g/h bug. the extra logic path was an error at 3-body and above. basically, it summed the two highest-body contributions, not all body contributions
• when vmfc active for single-level, add nocp (and cp if full-body) since it's free. this makes the test qcvar lists a little contorted b/c 1b multilevel and 2b "22" multilevel are actually single-level
• make the properties only show defined ones for dict and serialize so we aren't always storing hessians and pentamers, etc.

[codecov]

Codecov Report

Merging #8 (b8aeb2d) into main (b8f0645) will increase coverage by 2.40%.
The diff coverage is 50.00%.

Additional details and impacted files