Add Functions tab to the side navigation menu in Developer prespective

Description

In the developer perspective, in the left side navigation menu, add Functions tab inside Resources section, which will list down all the serverless functions created for the specific namepsace and on click of function, open the Service details tab

Acceptance Criteria

1. Add Functions tab in left navigation menu below inside Resources section
2. when user navigates to functions page, list all the serverless functions associated with that namespace
3. When user clicks on function name, user should see Details tab and YAML tab as presently available in service details page
4. In details page, add function URL which is already added in list page and add container section before Conditions(as present in Deployment details page)
5. Add e2e test

Additional Details: