Git import flow: Dockerfile is detected but file name is not used

Description of problem:

For a git repo where dockerfile is present but does not use the default filename(Dockerfile), the dockerfile is detected but that file name is not used in the dockerfile input field, which leaves the create button disabled.

Prerequisites (if any, like setup, operators/versions):

Any repository which has a dockerfile not using the default name. For example: https://github.com/rottencandy/flask-dockerfile-example

Steps to Reproduce

1. In git import flow, add the repo url
2. Open the import strategy section

Actual results:

The field is filled with the default name "Dockerfile", which is incorrect.

Expected results:

The detected dockerfile's name should be filled.

Reproducibility (Always/Intermittent/Only Once):

Always

Build Details:

4.9.0-0.nightly-2021-08-25-231643