Bug with email reports for internal errors

[vegu]

Describe the bug

Email report for internal errors appears to get get sent to incorrectly formatted recipient (u@peeringdb.com, u@peeringdb.com`)

This might be as simple as a configuration fix or might require code changes.

Looks like we are using django.utils.log.AdminEmailHandler which i believe uses the ADMINS setting to determine recipients.

[vegu]

As part of #715 we rolled out some fixes to how the ADMINS setting is specified (it was definitely broken before), will run some tests to see if that fixed the issue on beta.

During investigation of this we also found that it might make sense to expose a separate setting for an ops specific email to be used to dispatch error messages to. Currently it uses the SERVER_EMAIL setting which is set to support@peeringdb.com.

SERVER_EMAIL is also used to specify the sender for emails sent to users, so should not be changed.

[vegu]

Can confirm that #715 seems to have fixed the issue with the malformed recipient address which makes the remaining scope of this ticket io expose a separate setting called OPERATIONS_EMAIL for an ops specific email address to dispatch error messages to.