Update tree-sitter-json WASM build to latest

Spotted it falling down on a very large JSON file I had. Seems to be fixed on `master`. Not sure which verison I originally built it from.

Author: savetheclocktower

packages/language-json/grammars/modern-tree-sitter-json.cson

@@ -6,6 +6,7 @@ parser: 'tree-sitter-json'
 injectionRegex: "^(json|JSON)$"
 
 treeSitter:
+  parserSource: 'github:tree-sitter/tree-sitter-json#3fef30de8aee74600f25ec2e319b62a1a870d51e'
   grammar: 'tree-sitter/tree-sitter-json.wasm'
   highlightsQuery: 'tree-sitter/queries/highlights.scm'
   indentsQuery: 'tree-sitter/queries/indents.scm'