DOCS-15730 Add planningTimeMicros to profiler output (#2353)

* DOCS-15730 Add planningTimeMicros to profiler output

* Internal feedback 1

* add query planning link

Author: ianf-mongodb

source/reference/database-profiler.txt

@@ -107,6 +107,7 @@ operations on a standalone:
                   "responseLength" : 1305014,
                   "protocol" : "op_msg",
                   "millis" : 69132,
+                  "planningTimeMicros" : 129,
                   "planSummary" : "IXSCAN { a: 1, _id: -1 }",
                   "execStats" : {
                      "stage" : "FETCH",
@@ -192,6 +193,7 @@ operations on a standalone:
                      }
                   },
                   "millis" : 164687,
+                  "planningTimeMicros" : 129,
                   "planSummary" : "COLLSCAN",
                   "execStats" : {
                      "stage" : "UPDATE",
@@ -668,6 +670,13 @@ operation.
    :binary:`~bin.mongod` from the beginning of the operation to the end of
    the operation.
 
+.. data:: planningTimeMicros
+   
+   .. versionadded:: 6.2
+
+   The time, in milliseconds, that the ``find`` or ``aggregate`` command 
+   spent in :ref:`query planning <query-plans-query-optimization>`.
+
 .. data:: system.profile.planSummary
 
    A summary of the execution plan.