Compact comment-skipping in sopsToGoSlice

The previous implementation pre-allocated `result` to `len(slice)`
and wrote each non-comment value at its source index. When the input
contained comments, the slots at those indices were left as `nil`,
producing arrays with embedded nil holes that downstream
`mapstructure` decoding would silently accept. Switch to an
`append`-based compaction loop, mirroring `flattenDescendArray` in
`flatten.go`, so that comments are dropped cleanly and indices on
the output remain contiguous.

No metadata array carries comments today, so this is a latent fix
rather than a behaviour change for any current input.

Signed-off-by: Hidde Beydals <hidde@hhh.computer>

Author: hiddeco

stores/metadata.go

@@ -47,16 +47,16 @@ func sopsToGoMap(mapping sops.TreeBranch) (map[string]interface{}, error) {
 }
 
 func sopsToGoSlice(slice []interface{}) ([]interface{}, error) {
-	result := make([]interface{}, len(slice))
-	for idx, item := range slice {
+	result := make([]interface{}, 0, len(slice))
+	for _, item := range slice {
 		if _, ok := item.(sops.Comment); ok {
 			continue
 		}
 		value, err := sopsToGo(item)
 		if err != nil {
 			return nil, err
 		}
-		result[idx] = value
+		result = append(result, value)
 	}
 	return result, nil
 }