Vscode-extension-for-zowe: Optional Credentials: Prompt* as value for Username and Password

[jellypuno]

I don't want to save my credentials in ZOWE CLI so I created a profile with --user prompt* and --pass prompt* so that whenever i use it, I will be prompted for my credentials.

The issue is that Zowe Explorer reads it as a regular user and password so I have a 401 error.

There are 2 possible fix for this:

1. To handle "prompt*" in the validation of promptCredentials()
2. Change the approach of Optional Credentials and create profiles with prompt* as values for user and password. So that whenever you use the profile with Optional Credentials you will be prompted both in Zowe Explorer or Zowe CLI.

[jellypuno]

Limitation: prompt* doesn't work in secure credential store 😞

[zFernand0]

I added an issue in the secure credential store plugin so that we don't forget about this. Will reference it once the plugin is contributed to Zowe 👍

[MikeBauerCA]

The Zowe CLI should be enhanced so that all profile fields are optional and when running a command if an option is not supplied and there is no default option, the user is prompted.

[jellypuno]

This issue was handled in v.1.6.0 "Fix failure to load optional secure fields from profiles."

Originally I have an issue with SCS so I wanted to implement this. But since @tjohnsonBCM implemented his change, this is no longer a problem.