appview: repo: update tagmap to work on annotated tags

annotated tags have their own custom hashes, but the "target" of the tag
points to the commit they refer to.

appview/state/repo.go

···
 	tagMap := make(map[string][]string)
 	for _, tag := range result.Tags {
 		hash := tag.Hash
+		if tag.Tag != nil {
+			hash = tag.Tag.Target.String()
+		}
 		tagMap[hash] = append(tagMap[hash], tag.Name)
 	}
 
···
 	tagMap := make(map[string][]string)
 	for _, tag := range result.Tags {
 		hash := tag.Hash
+		if tag.Tag != nil {
+			hash = tag.Tag.Target.String()
+		}
 		tagMap[hash] = append(tagMap[hash], tag.Name)
 	}