feat: support env tag in config (#2577)

* feat: support env tag in config

* chore: add more tests

* chore: add more tests, add stringx.Join

* fix: test fail

* chore: remove print code

* chore: rename variable

core/stringx/strings.go

@@ -69,6 +69,33 @@ func HasEmpty(args ...string) bool {
 	return false
 }
 
+// Join joins any number of elements into a single string, separating them with given sep.
+// Empty elements are ignored. However, if the argument list is empty or all its elements are empty,
+// Join returns an empty string.
+func Join(sep byte, elem ...string) string {
+	var size int
+	for _, e := range elem {
+		size += len(e)
+	}
+	if size == 0 {
+		return ""
+	}
+
+	buf := make([]byte, 0, size+len(elem)-1)
+	for _, e := range elem {
+		if len(e) == 0 {
+			continue
+		}
+
+		if len(buf) > 0 {
+			buf = append(buf, sep)
+		}
+		buf = append(buf, e...)
+	}
+
+	return string(buf)
+}
+
 // NotEmpty checks if all strings are not empty in args.
 func NotEmpty(args ...string) bool {
 	return !HasEmpty(args...)