adjust linter warnings

Author: phryneas

src/jsutils/ObjMap.ts

@@ -1,6 +1,6 @@
 /**
  * Quoted as "used by external libraries".
- * All of these could be replaced by Record<string, T> or Readonly<Record<string, T>>
+ * All of these could be replaced by Record\<string, T\> or Readonly\<Record\<string, T\>\>
  * Should we still expose these?
  */