Fixing formattedMessage bug

[RohitRanjanMS]

Fixing formattedMessage sanitize logic.

Pull request checklist

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Additional information

Additional PR information

[jviau]

We need to ensure that formattedMessage has either a value or empty string. Sanitizer.Sanitize checks that and we will return early if formattedMessage is one of those so LGTM!

The sanitize only happens if there is an exception. We need to ensure it is non-null in other scenarios.

[cjaliaga]

We need to ensure that formattedMessage has either a value or empty string. Sanitizer.Sanitize checks that and we will return early if formattedMessage is one of those so LGTM!

The sanitize only happens if there is an exception. We need to ensure it is non-null in other scenarios.

Reading it now, it doesn't say what I wanted to say 🥲. I mean that Sanitizer.Sanitize checks that and that we also return early here, so we should be covered:

https://github.com/Azure/azure-functions-host/blob/351083550777eadf9fe793823ea03d7be1c33e00/src/WebJobs.Script.WebHost/Diagnostics/SystemLogger.cs#L122-L125