Fix EnableISEMode for Azure Data Studio

[andyleejordan]

Because ADS stripped out VS Code's debugger, the debug settings don't
exist, causing our update() call for the debug setting to throw an
error to the user when they run EnableISEMode. I couldn't find a
reliable way to test if the extension is running in the ADS fork instead
of the upstream VS Code, but a simple try {} catch {} that allows the
funciton to continue is a reliable fix, as we can't do anything about
this setting regardless.

Resolves #3709.

[andyleejordan]

/cc @Charles-Gagnon

[Charles-Gagnon]

Thanks for fixing @andschwa !

There's a couple options for determining if it's running in ADS :

1. You can check at runtime whether the azdata API object exists - such as what we do here : https://github.com/microsoft/azuredatastudio/blob/main/extensions/data-workspace/src/common/utils.ts#L54
2. vscode.env.appName is another option (it should be Azure Data Studio for ADS) Note though that this may not be the best option as other versions of the app such as insiders may have a slightly different name.

Although unless you find another case that you can't easily solve like this one it's probably easiest to just leave it as this. Although I would suggest adding a log statement or something in the catch so you can see what settings were ignored in case a setting is erroring that you don't expect.

[andyleejordan]

Thanks so much @Charles-Gagnon, you're always so helpful!