bareos-fd-postgres: properly close database connection

[lluuaapp]

This will properly close the database connection after a Postgres WAL backup was made. As far as I could see a call to close() is completely missing in the current code. As the the connection may already been closed I put it in a try/except to ignore all errors that may occur.

On my test system this prevents the PostgreSQL server to log

unexpected EOF on client connection with an open transaction

every backup.

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[arogge]

Thank you very much for taking the time to improve Bareos!

We usually fix things in master and then backport to the release branches. Would you mind changing your PR to target the master branch? We can add a "requires backport" label to the PR (and we can probably handle the backport for you)

Also, if you don't mind - would you rename the existing closeDbConnection() to something reasonable? It isn't really about closing the connection.

[arogge]

I'm not really happy with that. I guess we're only expecting a "connection already closed" exception and thus we should only catch that one.

[lluuaapp]

Seems than I can not change the target branch of a PR. I will close this one and create a new one from master -> master.

[lluuaapp]

This is the new PR: #1326