Fix redundant "" when sending messages (Note: string types should use FormBuilder::add_raw instead of FormBuiolder::add)

src/core/requests/form_builder.rs

@@ -45,6 +45,17 @@ impl FormBuilder {
         }
     }
 
+    /// Add the supplied key-value pair to this `FormBuilder`.
+    /// With raw str value, so `serde_json` will not add redundant `""`
+    pub fn add_raw(self, name: &str, value: &str) -> Self {
+        Self {
+            form: self.form.text(
+                name.to_owned(),
+                value.to_owned(),
+            ),
+        }
+    }
+
     pub fn build(self) -> Form {
         self.form
     }

src/core/requests/send_message.rs

@@ -25,7 +25,7 @@ impl<'a> Request<'a> for SendMessage<'a> {
         Box::pin(async move {
             let params = FormBuilder::new()
                 .add("chat_id", &self.chat_id)
-                .add("text", &self.text)
+                .add_raw("text", &self.text)
                 .add_if_some("parse_mode", self.parse_mode.as_ref())
                 .add_if_some(
                     "disable_web_page_preview",