Move Learning MFE Header to frontend-component-header MFE

[asadiqbal08]

Related to #112

As per some suggestion by David, We need to refactor the code in EdX Learning MFE to utlize the header from frontend-component-header instead of course-header

Acceptance Criteria:

Create an upstream PR to edx frontend-component-header repository with the following criteria

• Move the course-header code inside the src directory of frontend-component-header (May be custom directory with name of /src/headers and introduce this course-header as LearningHeader there and can be used to add new header as StudioHeader in future.
• Looked around some other dependency course-header in the Learning MFE repository and move those dependency along it such as generic ?
• frontend-component-header MFE should export this new header LearningHeader
  - [ ] frontend-component-header MFE should export the CourseTabsNavigation component.
• We'd also need to copy that code into frontend-component-header-edx so that edx.org's build process doesn't explode, since the site runs on master
• Header Tests (or others) should be passed after the refactoring.

#### Once the Code integrated in frontend-component-header and frontend-component-header-edx
#### NOTE: We can move the below details into another story.

Create an upstream PR to frontend-app-learning repository with the following criteria:
- [ ] The code related to course-header should be removed from the repository.
- [ ] Introduced the @edx/frontend-component-header in package.json.
- [ ] Import the header import { LearningHeader as Header } from '@edx/frontend-component-header'; instead of import { Header } from '../course-header';

NOTE: After that, we will be able to use the npm aliases as described.~~

Out of Scope

• ?????

[asadiqbal08]

@pdpinch FYI

[davidjoy]

Hi there - I'd suggest that CourseTabsNavigation stay in the learning MFE - its very specific to that application and is used outside/below the main header. I think we want to limit what we pull over to frontend-component-header to be the top-most Header. Most of the sub-components of it will be able to share code with the other Headers we put in frontend-component-header as we go forward.

Feel free to tag me if I can help answer questions here - this was brought up in the Frontend Working Group's meeting today, where we were pleased to see this issue!

[davidjoy]

Another note - I think if we leave CourseTabsNavigation behind, we can get away without moving anything from generic as well. If we have things in generic that we really want to start using across MFEs or libraries, we may want to consider moving them to https://github.com/edx/paragon rather than duplicating them into frontend-component-header.

[asadiqbal08]

@davidjoy Thanks for the input. I will try to create an upstream PR first for the some possible changes in frontend-component-header.