Issue Type: <b>Bug</b>

Git Fetch for Remote SSH project which does not have SSH credentials configured fails for Git Fetch. Says "Missing or invalid credentials" though username/password was never prompted.

VS Code version: Code 1.39.2 (6ab598523be7a800d7f3eb4d92d7ab9a66069390, 2019-10-15T15:35:18.241Z) OS version: Windows_NT x64 10.0.18362 Remote OS version: Linux x64 4.1.12-124.32.1.el7uek.x86_64

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