Autocomplete dropdown

[jincypjose]

Just to keep the track of work done in a collaboration week. A note from @klappy
I'm thinking we could start with some mock components, and then populate them later.

1. OrganizationsSelection
2. RepositoriesSelection
3. Branch/TagSelection
4. FilepathSelection

• For now we can just list a few mock strings for each in the selection.
• When we're done with the mock data, each component should do the fetching of the list of options via the corresponding DCS React Hook
• Each component should save the selection in the corresponding state the hook that we already created (or applcation state).
• Once organization, repository, branch/tag, and filepath are populated in the application state as strings, then we can generate the url strings.
• We should be able to reuse the components above to populate the old/new urls.

To simplify, we may be able to just handle one organization, repository and filepath. Then each side, old/new, gets to select branch/tag.
This limits the use case but is easier to implement and handles our most common use cases.

[jincypjose]

This can be considered as an Epic

[jincypjose]

This issue belongs to diff Tool.