Bugfix: SBDB query return unit with exponentials

[jianyangli]

When SBDB query returns quantities that have units with exponentials, an error is issued because '^' is used to mark exponentials instead of '**' in the unit strings. Issue #2368 . This PR fixes this bug.

[codecov]

Codecov Report

Merging #2377 (6329863) into main (d53047b) will increase coverage by 0.00%.
The diff coverage is 75.00%.

@@           Coverage Diff           @@
##             main    #2377   +/-   ##
=======================================
  Coverage   63.29%   63.29%           
=======================================
  Files         132      132           
  Lines       17241    17245    +4     
=======================================
+ Hits        10913    10916    +3     
- Misses       6328     6329    +1     

Impacted Files	Coverage Δ
astroquery/jplsbdb/core.py	78.61% <75.00%> (-0.09%)	⬇️

📣 Codecov can now indicate which changes are the most critical in Pull Requests. Learn more

[bsipocz]

Please add a changelog entry, otherwise, it looks good to me.

I would wait a few days with the merge though to give a chance for Mike to review it, too.

[jianyangli]

I don't understand the failing check. CHANGES.rst was what I changed in the last two commits. Why did astropy-bot complain it's missing? Could someone help?

[bsipocz]

@jianyangli - The changelog needs the number of the PR rather than the issue referenced. Don't worry about it, I can fix up the changelog before releasing. apparently I was wrong, it rather looks like a fluke with the changelog bot.

[ceb8]

Thanks @jianyangli!