Update relog.md

Adding COM dependency explanation for relog function

Author: laurenprinn

docs/build-insights/reference/sdk/functions/relog.md

@@ -77,4 +77,6 @@ The input trace is passed through the analyzer group *numberOfAnalysisPasses* ti
 
 The relogging of system events like CPU samples from within a relogger class isn't supported. Use the *systemEventsRetentionFlags* parameter to decide which system events to keep in the output trace.
 
+The `relog` function depends on the COM API, so it is necessary for the user to call the [`CoInitialize`](https://learn.microsoft.com/en-us/windows/win32/api/objbase/nf-objbase-coinitialize) first and then [`CoUninitialize`](https://learn.microsoft.com/en-us/windows/win32/api/combaseapi/nf-combaseapi-couninitialize) once `relog` has finished. If you call `relog` without calling `CoInitialize` first then you will get error code 9 (RESULT_CODE_FAILURE_START_RELOGGER).
+
 ::: moniker-end