feat: enable compression on zip dump (#12296)

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Reviewed-on: https://codeberg.org/forgejo/forgejo/pulls/12296
Reviewed-by: Gusted <gusted@noreply.codeberg.org>
Reviewed-by: Mathieu Fenniak <mfenniak@noreply.codeberg.org>

cmd/dump.go

@@ -112,7 +112,10 @@ func getArchiverByType(outType string) (archives.ArchiverAsync, error) {
 	var archiver archives.ArchiverAsync
 	switch outType {
 	case "zip":
-		archiver = archives.Zip{}
+		archiver = archives.Zip{
+			Compression:          8,
+			SelectiveCompression: false,
+		}
 	case "tar":
 		archiver = archives.Tar{}
 	case "tar.sz":