Mangled AAR header when srv_id is a suffix of some AR header fields

[Nikolay]

Here's an example of the generated AAR header from the existing AR header (produced by ARC.sign method):

ARC-Authentication-Results: i=1; 10-69-43-116.qa.plesk.tech; dmarc=pass (p=QUARANTINE sp=NONE) smtp.from=test1.10-69-43-116.qa.plesk.tech header.from=test1.
        dkim=pass header.d=test1.
        spf=pass (sender IP is 127.0.0.1) <email address hidden> smtp.helo=webmail.test1.10-69-43-116.qa.plesk.tech
Authentication-Results: 10-69-43-116.qa.plesk.tech;
        dmarc=pass (p=QUARANTINE sp=NONE) smtp.from=test1.10-69-43-116.qa.plesk.tech header.from=test1.10-69-43-116.qa.plesk.tech;
        dkim=pass header.d=test1.10-69-43-116.qa.plesk.tech;
        spf=pass (sender IP is 127.0.0.1) <email address hidden> smtp.helo=webmail.test1.10-69-43-116.qa.plesk.tech

Note that some semicolons are missing and trailing parts of header.from and header.d are missing as well. For the purposes of this result srv_id = b'10-69-43-116.qa.plesk.tech' in the call to the library.

I believe this can be fixed by the following change in the library code:

- results_lists = [raw.replace(srv_id + b';', b'').strip() for (raw, parsed) in auth_headers]
+ results_lists = [raw.replace(srv_id + b';', b'', 1).strip() for (raw, parsed) in auth_headers]

Library version: dkimpy==1.1.5

Original API call:

r = arc.sign('default'.encode(), 'test1.10-69-43-116.qa.plesk.tech'.encode(), key, '10-69-43-116.qa.plesk.tech'.encode())