Correct property name to pid

docs/api/structures/memory-info.md

@@ -1,6 +1,6 @@
 # MemoryInfo Object
 
-* `workingSetSize` Integer - Process id of the process.
+* `pid` Integer - Process id of the process.
 * `workingSetSize` Integer - The amount of memory currently pinned to actual physical RAM.
 * `peakWorkingSetSize` Integer - The maximum amount of memory that has ever been pinned
   to actual physical RAM.
@@ -9,4 +9,4 @@
 * `sharedBytes` Integer - The amount of memory shared between processes, typically
   memory consumed by the Electron code itself
 
-Note that all statistics are reported in Kilobytes.
+Note that all statistics are reported in Kilobytes.