remove decimal default feature

Author: baoyachi

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "duration-str"
-version = "0.3.1"
+version = "0.3.2"
 authors = ["baoyachi <liaoymxsdl@gmail.com>"]
 edition = "2018"
 description = "duration string parser"
@@ -19,7 +19,7 @@ anyhow = "1.0.38"
 chrono = { version = "0.4.19", optional = true }
 serde = { version = "1.0.124", features = ["derive"], optional = true }
 serde_json = { version = "1.0.64", optional = true }
-rust_decimal = "1.15"
+rust_decimal = { version = "1.15", default-features = false }
 
 [features]
-default = ["chrono","serde","serde_json"]
+default = ["chrono", "serde", "serde_json"]