Terminal errors don't correctly complete a refresh operation

[enocom]

See GoogleCloudPlatform/alloydb-java-connector#669 where we discovered that a terminal exception will leave the refresh operation operation state with refreshRunning set to true. This prevents future connection attempts from succeeding once the terminal state has resolved.

Key fix is here:

https://github.com/GoogleCloudPlatform/cloud-sql-jdbc-socket-factory/blob/main/core/src/main/java/com/google/cloud/sql/core/RefreshAheadStrategy.java#L277-L280

There needs to be this:

synchronized (connectionInfoGuard) {
          refreshRunning = false;
}

[kgala2]

Thanks for pointing this out, I will fix this for cloud-sql-jdbc