Deal with error: `connection already closed`

[khoroshevskyi]

Now if connection is closed, pepdbagent won't fail, nor fix it. We should fix this error. 2 ways of fixing it:

• throw an exception if this condition occurs.
• Reconnect to db.

@nleroy917 what do you think is better solution?

linked to: https://github.com/pepkit/geo_pephub/issues/3

[khoroshevskyi]

I think it's not a problem anymore