Add test cases for nested record field access

Connects #81

test/corpus/expressions.txt

@@ -145,3 +145,18 @@ panic as { "Hello, " <> "world!" }
           (quoted_content))
         (string
           (quoted_content))))))
+
+================================================================================
+Nested field access
+================================================================================
+
+config.connection.host
+
+--------------------------------------------------------------------------------
+
+(source_file
+  (field_access
+    (field_access
+      (identifier)
+      (label))
+    (label)))

test/highlight/records.gleam

@@ -12,3 +12,9 @@ pub fn new(name: String) {
   //    ^ property
   //          ^ variable.parameter
 }
+
+let config = Config()
+config.connection.host
+// ^ variable
+//       ^ property
+//                 ^ property