Remove maplit dependency and stop using a macro for hashmaps (#982)

src/snapshot_middleware/json.rs

@@ -1,7 +1,6 @@
 use std::path::Path;
 
 use anyhow::Context;
-use maplit::hashmap;
 use memofs::{IoResultExt, Vfs};
 
 use crate::{
@@ -24,9 +23,7 @@ pub fn snapshot_json(
 
     let as_lua = json_to_lua(value).to_string();
 
-    let properties = hashmap! {
-        "Source".to_owned() => as_lua.into(),
-    };
+    let properties = [("Source".to_owned(), as_lua.into())];
 
     let meta_path = path.with_file_name(format!("{}.meta.json", name));