ZE activation and commands fail when team config contains JSON error

[t1m0thyj]

I am seeing issues when a user has a team config that contains a json error.

Issue 1:

1. Start with a good config.
2. Launch VS Code.
3. Edit the config and introduce a json error (e.g., add a bracket)
4. Right click on a profile in the trees, select Manage Profile, then select Edit Profile. (the same behavior will also occur if you try to search for data sets)
5. You will receive an error that says you have a json error, but you won't be shown your team config.

This happens in 2.17 as well.

Issue 2 (new to 2.18):

1. Start with a config that contains a json error.
2. Launch VS Code.
3. You will get an error message saying that you have a json error in your team config.
4. Click the + button to add a profile to one of the trees.
5. You will get an error message: Error running command zowe.ds.addSession: command 'zowe.ds.addSession' not found. This is likely caused by the extension that contributes zowe.ds.addSession.

In 2.18, you are never given the option to "Show config" if you launch VS Code with a team config that contains an error.

Originally posted by @adam-wolfe in #3063 (review)