UI - Workflow credential - Provide easier way to enter credentials (may be drop down of tool name that requires auth).

[sangee2004]

Steps to reproduce the problem:

1. Create a workflow with credential.
2. Notice that I have to enter a credential as a tool url to a specific tool's credential like - github.com/otto8-ai/tools/github/credential.

Expected Behavior:
Having to enter credential as a tool url to a specific tool's credential is error prone.
Can we provide a drop down option with all tools (that require credentials) that user can pick instead?

[cjellick]

not changing this.