git: Add configured SSL certificate for SMTP (#1833)

If you have a custom SSL certificate configured for SMTP TLS, git should
use it.

tests/modules/programs/git/git-with-email-expected.conf

@@ -2,12 +2,14 @@
 	from = "hm@example.org"
 	smtpEncryption = "tls"
 	smtpServer = "smtp.example.org"
+	smtpSslCertPath = "/etc/test/certificates.crt"
 	smtpUser = "home.manager.jr"
 
 [sendemail "hm@example.com"]
 	from = "hm@example.com"
 	smtpEncryption = "ssl"
 	smtpServer = "smtp.example.com"
+	smtpSslCertPath = "/etc/ssl/certs/ca-certificates.crt"
 	smtpUser = "home.manager"
 
 [user]

tests/modules/programs/git/git-with-email.nix

@@ -6,6 +6,8 @@ with lib;
   imports = [ ../../accounts/email-test-accounts.nix ];
 
   config = {
+    accounts.email.accounts.hm-account.smtp.tls.certificatesFile =
+      "/etc/test/certificates.crt";
     programs.git = {
       enable = true;
       package = pkgs.gitMinimal;

tests/modules/programs/git/git-with-msmtp-expected.conf

@@ -2,6 +2,7 @@
 	from = "hm@example.org"
 	smtpEncryption = "tls"
 	smtpServer = "smtp.example.org"
+	smtpSslCertPath = "/etc/ssl/certs/ca-certificates.crt"
 	smtpUser = "home.manager.jr"
 
 [sendemail "hm@example.com"]