git: gpg sign tags with signing.signByDefault set

The `tag.gpgSign` config option was added in Git 2.23.0 and seems like
it should be set in addition to `commit.gpgSign` when
`programs.git.signing.signByDefault` is enabled

modules/programs/git.nix

@@ -73,7 +73,7 @@ let
       signByDefault = mkOption {
         type = types.bool;
         default = false;
-        description = "Whether commits should be signed by default.";
+        description = "Whether commits and tags should be signed by default.";
       };
 
       gpgPath = mkOption {
@@ -444,6 +444,7 @@ in {
       programs.git.iniContent = {
         user.signingKey = mkIf (cfg.signing.key != null) cfg.signing.key;
         commit.gpgSign = cfg.signing.signByDefault;
+        tag.gpgSign = cfg.signing.signByDefault;
         gpg.program = cfg.signing.gpgPath;
       };
     })

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

@@ -43,6 +43,9 @@
 [interactive]
 	diffFilter = "@delta@/bin/delta --color-only"
 
+[tag]
+	gpgSign = true
+
 [user]
 	email = "user@example.org"
 	name = "John Doe"

tests/modules/programs/git/git-with-signing-key-id-expected.conf

@@ -4,6 +4,9 @@
 [gpg]
 	program = "path-to-gpg"
 
+[tag]
+	gpgSign = true
+
 [user]
 	email = "user@example.org"
 	name = "John Doe"

tests/modules/programs/git/git-without-signing-key-id-expected.conf

@@ -4,6 +4,9 @@
 [gpg]
 	program = "path-to-gpg"
 
+[tag]
+	gpgSign = true
+
 [user]
 	email = "user@example.org"
 	name = "John Doe"