Miscellaneous first checks

• I checked that all ports are open and not blocked by my ISP / hosting provider.
• I know that SSL errors are likely the result of a wrong setup on the user side and not caused by DMS itself. I'm confident my setup is correct.

Affected Component(s)

postfix

What happened and when does this occur?

virtual_alias_maps ends up with multiple `pcre:/etc/postfix/regexp` entries

What did you expect to happen?

Only a single entry

How do we replicate the issue?

1. Start dms
2. create data/config/postfix-regexp.cf
2. edit the alias file; wait one second
3. edit the alias file; again

DMS version

edge

What operating system is DMS running on?

Linux

What instruction set architecture is DMS running on?

x86_64 / AMD64

What container orchestration tool are you using?

Docker

docker-compose.yml

No response

Relevant log output

No response

Other relevant information

The sed line in `_handle_postfix_regexp_config` that adds the config to `virtual_alias_maps` is not guarded by a check to see if it is already present in the file. 

I think it may be possible to just always include the `pcre:/etc/postfix/regexp` as `_handle_postfix_virtual_config` always creates that file as empty.

What level of experience do you have with Docker and mail servers?

• I am inexperienced with docker
• I am inexperienced with mail servers
• I am uncomfortable with the CLI

Code of conduct

• I have read this project's Code of Conduct and I agree
• I have read the README and the documentation and I searched the issue tracker but could not find a solution

Improvements to this form?

No response