[idea] Create a new test on UI by copy and paste test yml definition

[danielbdias]

Describe the enhancement you'd like to see

Sometimes a user could try to replicate a test that they saw in a Tracetest documentation or blog post. Or even get a definition of a big test that he did on the interface and create a copy with some changes.

Today we can do that only by copying the YAML definition to a file, running it through the CLI and later going to the Web UI and editing the test.

[danielbdias]

Closing this issue in favor of #3062, which follows this idea in a user-friendly way.